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ruby--ruby/enumerator.c
Jeremy Evans ffd0820ab3 Deprecate taint/trust and related methods, and make the methods no-ops
This removes the related tests, and puts the related specs behind
version guards.  This affects all code in lib, including some
libraries that may want to support older versions of Ruby.
2019-11-18 01:00:25 +02:00

4127 lines
104 KiB
C

/************************************************
enumerator.c - provides Enumerator class
$Author$
Copyright (C) 2001-2003 Akinori MUSHA
$Idaemons: /home/cvs/rb/enumerator/enumerator.c,v 1.1.1.1 2001/07/15 10:12:48 knu Exp $
$RoughId: enumerator.c,v 1.6 2003/07/27 11:03:24 nobu Exp $
$Id$
************************************************/
#include "ruby/ruby.h"
#include "internal.h"
#include "id.h"
#ifdef HAVE_FLOAT_H
#include <float.h>
#endif
/*
* Document-class: Enumerator
*
* A class which allows both internal and external iteration.
*
* An Enumerator can be created by the following methods.
* - Object#to_enum
* - Object#enum_for
* - Enumerator.new
*
* Most methods have two forms: a block form where the contents
* are evaluated for each item in the enumeration, and a non-block form
* which returns a new Enumerator wrapping the iteration.
*
* enumerator = %w(one two three).each
* puts enumerator.class # => Enumerator
*
* enumerator.each_with_object("foo") do |item, obj|
* puts "#{obj}: #{item}"
* end
*
* # foo: one
* # foo: two
* # foo: three
*
* enum_with_obj = enumerator.each_with_object("foo")
* puts enum_with_obj.class # => Enumerator
*
* enum_with_obj.each do |item, obj|
* puts "#{obj}: #{item}"
* end
*
* # foo: one
* # foo: two
* # foo: three
*
* This allows you to chain Enumerators together. For example, you
* can map a list's elements to strings containing the index
* and the element as a string via:
*
* puts %w[foo bar baz].map.with_index { |w, i| "#{i}:#{w}" }
* # => ["0:foo", "1:bar", "2:baz"]
*
* An Enumerator can also be used as an external iterator.
* For example, Enumerator#next returns the next value of the iterator
* or raises StopIteration if the Enumerator is at the end.
*
* e = [1,2,3].each # returns an enumerator object.
* puts e.next # => 1
* puts e.next # => 2
* puts e.next # => 3
* puts e.next # raises StopIteration
*
* You can use this to implement an internal iterator as follows:
*
* def ext_each(e)
* while true
* begin
* vs = e.next_values
* rescue StopIteration
* return $!.result
* end
* y = yield(*vs)
* e.feed y
* end
* end
*
* o = Object.new
*
* def o.each
* puts yield
* puts yield(1)
* puts yield(1, 2)
* 3
* end
*
* # use o.each as an internal iterator directly.
* puts o.each {|*x| puts x; [:b, *x] }
* # => [], [:b], [1], [:b, 1], [1, 2], [:b, 1, 2], 3
*
* # convert o.each to an external iterator for
* # implementing an internal iterator.
* puts ext_each(o.to_enum) {|*x| puts x; [:b, *x] }
* # => [], [:b], [1], [:b, 1], [1, 2], [:b, 1, 2], 3
*
*/
VALUE rb_cEnumerator;
static VALUE rb_cLazy;
static ID id_rewind, id_new, id_to_enum;
static ID id_next, id_result, id_receiver, id_arguments, id_memo, id_method, id_force;
static ID id_begin, id_end, id_step, id_exclude_end;
static VALUE sym_each, sym_cycle, sym_yield;
static VALUE lazy_use_super_method;
#define id_call idCall
#define id_each idEach
#define id_eqq idEqq
#define id_initialize idInitialize
#define id_size idSize
VALUE rb_eStopIteration;
struct enumerator {
VALUE obj;
ID meth;
VALUE args;
VALUE fib;
VALUE dst;
VALUE lookahead;
VALUE feedvalue;
VALUE stop_exc;
VALUE size;
VALUE procs;
rb_enumerator_size_func *size_fn;
int kw_splat;
};
static VALUE rb_cGenerator, rb_cYielder, rb_cEnumProducer;
struct generator {
VALUE proc;
VALUE obj;
};
struct yielder {
VALUE proc;
};
struct producer {
VALUE init;
VALUE proc;
};
typedef struct MEMO *lazyenum_proc_func(VALUE, struct MEMO *, VALUE, long);
typedef VALUE lazyenum_size_func(VALUE, VALUE);
typedef struct {
lazyenum_proc_func *proc;
lazyenum_size_func *size;
} lazyenum_funcs;
struct proc_entry {
VALUE proc;
VALUE memo;
const lazyenum_funcs *fn;
};
static VALUE generator_allocate(VALUE klass);
static VALUE generator_init(VALUE obj, VALUE proc);
static VALUE rb_cEnumChain;
struct enum_chain {
VALUE enums;
long pos;
};
VALUE rb_cArithSeq;
/*
* Enumerator
*/
static void
enumerator_mark(void *p)
{
struct enumerator *ptr = p;
rb_gc_mark_movable(ptr->obj);
rb_gc_mark_movable(ptr->args);
rb_gc_mark_movable(ptr->fib);
rb_gc_mark_movable(ptr->dst);
rb_gc_mark_movable(ptr->lookahead);
rb_gc_mark_movable(ptr->feedvalue);
rb_gc_mark_movable(ptr->stop_exc);
rb_gc_mark_movable(ptr->size);
rb_gc_mark_movable(ptr->procs);
}
static void
enumerator_compact(void *p)
{
struct enumerator *ptr = p;
ptr->obj = rb_gc_location(ptr->obj);
ptr->args = rb_gc_location(ptr->args);
ptr->fib = rb_gc_location(ptr->fib);
ptr->dst = rb_gc_location(ptr->dst);
ptr->lookahead = rb_gc_location(ptr->lookahead);
ptr->feedvalue = rb_gc_location(ptr->feedvalue);
ptr->stop_exc = rb_gc_location(ptr->stop_exc);
ptr->size = rb_gc_location(ptr->size);
ptr->procs = rb_gc_location(ptr->procs);
}
#define enumerator_free RUBY_TYPED_DEFAULT_FREE
static size_t
enumerator_memsize(const void *p)
{
return sizeof(struct enumerator);
}
static const rb_data_type_t enumerator_data_type = {
"enumerator",
{
enumerator_mark,
enumerator_free,
enumerator_memsize,
enumerator_compact,
},
0, 0, RUBY_TYPED_FREE_IMMEDIATELY
};
static struct enumerator *
enumerator_ptr(VALUE obj)
{
struct enumerator *ptr;
TypedData_Get_Struct(obj, struct enumerator, &enumerator_data_type, ptr);
if (!ptr || ptr->obj == Qundef) {
rb_raise(rb_eArgError, "uninitialized enumerator");
}
return ptr;
}
static void
proc_entry_mark(void *p)
{
struct proc_entry *ptr = p;
rb_gc_mark_movable(ptr->proc);
rb_gc_mark_movable(ptr->memo);
}
static void
proc_entry_compact(void *p)
{
struct proc_entry *ptr = p;
ptr->proc = rb_gc_location(ptr->proc);
ptr->memo = rb_gc_location(ptr->memo);
}
#define proc_entry_free RUBY_TYPED_DEFAULT_FREE
static size_t
proc_entry_memsize(const void *p)
{
return p ? sizeof(struct proc_entry) : 0;
}
static const rb_data_type_t proc_entry_data_type = {
"proc_entry",
{
proc_entry_mark,
proc_entry_free,
proc_entry_memsize,
proc_entry_compact,
},
};
static struct proc_entry *
proc_entry_ptr(VALUE proc_entry)
{
struct proc_entry *ptr;
TypedData_Get_Struct(proc_entry, struct proc_entry, &proc_entry_data_type, ptr);
return ptr;
}
/*
* call-seq:
* obj.to_enum(method = :each, *args) -> enum
* obj.enum_for(method = :each, *args) -> enum
* obj.to_enum(method = :each, *args) {|*args| block} -> enum
* obj.enum_for(method = :each, *args){|*args| block} -> enum
*
* Creates a new Enumerator which will enumerate by calling +method+ on
* +obj+, passing +args+ if any. What was _yielded_ by method becomes
* values of enumerator.
*
* If a block is given, it will be used to calculate the size of
* the enumerator without the need to iterate it (see Enumerator#size).
*
* === Examples
*
* str = "xyz"
*
* enum = str.enum_for(:each_byte)
* enum.each { |b| puts b }
* # => 120
* # => 121
* # => 122
*
* # protect an array from being modified by some_method
* a = [1, 2, 3]
* some_method(a.to_enum)
*
* # String#split in block form is more memory-effective:
* very_large_string.to_enum(:split, "|") { |chunk| return chunk if chunk.include?('DATE') }
* # This could be rewritten more idiomatically with to_enum:
* very_large_string.to_enum(:split, "|").lazy.grep(/DATE/).first
*
* It is typical to call to_enum when defining methods for
* a generic Enumerable, in case no block is passed.
*
* Here is such an example, with parameter passing and a sizing block:
*
* module Enumerable
* # a generic method to repeat the values of any enumerable
* def repeat(n)
* raise ArgumentError, "#{n} is negative!" if n < 0
* unless block_given?
* return to_enum(__method__, n) do # __method__ is :repeat here
* sz = size # Call size and multiply by n...
* sz * n if sz # but return nil if size itself is nil
* end
* end
* each do |*val|
* n.times { yield *val }
* end
* end
* end
*
* %i[hello world].repeat(2) { |w| puts w }
* # => Prints 'hello', 'hello', 'world', 'world'
* enum = (1..14).repeat(3)
* # => returns an Enumerator when called without a block
* enum.first(4) # => [1, 1, 1, 2]
* enum.size # => 42
*/
static VALUE
obj_to_enum(int argc, VALUE *argv, VALUE obj)
{
VALUE enumerator, meth = sym_each;
if (argc > 0) {
--argc;
meth = *argv++;
}
enumerator = rb_enumeratorize_with_size(obj, meth, argc, argv, 0);
if (rb_block_given_p()) {
enumerator_ptr(enumerator)->size = rb_block_proc();
}
return enumerator;
}
static VALUE
enumerator_allocate(VALUE klass)
{
struct enumerator *ptr;
VALUE enum_obj;
enum_obj = TypedData_Make_Struct(klass, struct enumerator, &enumerator_data_type, ptr);
ptr->obj = Qundef;
return enum_obj;
}
#define PASS_KW_SPLAT (rb_empty_keyword_given_p() ? RB_PASS_EMPTY_KEYWORDS : rb_keyword_given_p())
static VALUE
enumerator_init(VALUE enum_obj, VALUE obj, VALUE meth, int argc, const VALUE *argv, rb_enumerator_size_func *size_fn, VALUE size, int kw_splat)
{
struct enumerator *ptr;
rb_check_frozen(enum_obj);
TypedData_Get_Struct(enum_obj, struct enumerator, &enumerator_data_type, ptr);
if (!ptr) {
rb_raise(rb_eArgError, "unallocated enumerator");
}
ptr->obj = obj;
ptr->meth = rb_to_id(meth);
if (argc) ptr->args = rb_ary_new4(argc, argv);
ptr->fib = 0;
ptr->dst = Qnil;
ptr->lookahead = Qundef;
ptr->feedvalue = Qundef;
ptr->stop_exc = Qfalse;
ptr->size = size;
ptr->size_fn = size_fn;
ptr->kw_splat = kw_splat;
return enum_obj;
}
/*
* call-seq:
* Enumerator.new(size = nil) { |yielder| ... }
* Enumerator.new(obj, method = :each, *args)
*
* Creates a new Enumerator object, which can be used as an
* Enumerable.
*
* In the first form, iteration is defined by the given block, in
* which a "yielder" object, given as block parameter, can be used to
* yield a value by calling the +yield+ method (aliased as +<<+):
*
* fib = Enumerator.new do |y|
* a = b = 1
* loop do
* y << a
* a, b = b, a + b
* end
* end
*
* p fib.take(10) # => [1, 1, 2, 3, 5, 8, 13, 21, 34, 55]
*
* The optional parameter can be used to specify how to calculate the size
* in a lazy fashion (see Enumerator#size). It can either be a value or
* a callable object.
*
* In the second, deprecated, form, a generated Enumerator iterates over the
* given object using the given method with the given arguments passed.
*
* Use of this form is discouraged. Use Object#enum_for or Object#to_enum
* instead.
*
* e = Enumerator.new(ObjectSpace, :each_object)
* #-> ObjectSpace.enum_for(:each_object)
*
* e.select { |obj| obj.is_a?(Class) } #=> array of all classes
*
*/
static VALUE
enumerator_initialize(int argc, VALUE *argv, VALUE obj)
{
VALUE recv, meth = sym_each;
VALUE size = Qnil;
int kw_splat = 0;
if (rb_block_given_p()) {
rb_check_arity(argc, 0, 1);
recv = generator_init(generator_allocate(rb_cGenerator), rb_block_proc());
if (argc) {
if (NIL_P(argv[0]) || rb_respond_to(argv[0], id_call) ||
(RB_TYPE_P(argv[0], T_FLOAT) && RFLOAT_VALUE(argv[0]) == HUGE_VAL)) {
size = argv[0];
}
else {
size = rb_to_int(argv[0]);
}
argc = 0;
}
}
else {
rb_check_arity(argc, 1, UNLIMITED_ARGUMENTS);
rb_warn("Enumerator.new without a block is deprecated; use Object#to_enum");
recv = *argv++;
if (--argc) {
meth = *argv++;
--argc;
}
kw_splat = PASS_KW_SPLAT;
}
return enumerator_init(obj, recv, meth, argc, argv, 0, size, kw_splat);
}
/* :nodoc: */
static VALUE
enumerator_init_copy(VALUE obj, VALUE orig)
{
struct enumerator *ptr0, *ptr1;
if (!OBJ_INIT_COPY(obj, orig)) return obj;
ptr0 = enumerator_ptr(orig);
if (ptr0->fib) {
/* Fibers cannot be copied */
rb_raise(rb_eTypeError, "can't copy execution context");
}
TypedData_Get_Struct(obj, struct enumerator, &enumerator_data_type, ptr1);
if (!ptr1) {
rb_raise(rb_eArgError, "unallocated enumerator");
}
ptr1->obj = ptr0->obj;
ptr1->meth = ptr0->meth;
ptr1->args = ptr0->args;
ptr1->fib = 0;
ptr1->lookahead = Qundef;
ptr1->feedvalue = Qundef;
ptr1->size = ptr0->size;
ptr1->size_fn = ptr0->size_fn;
return obj;
}
/*
* For backwards compatibility; use rb_enumeratorize_with_size
*/
VALUE
rb_enumeratorize(VALUE obj, VALUE meth, int argc, const VALUE *argv)
{
return rb_enumeratorize_with_size(obj, meth, argc, argv, 0);
}
static VALUE
lazy_to_enum_i(VALUE self, VALUE meth, int argc, const VALUE *argv, rb_enumerator_size_func *size_fn, int kw_splat);
VALUE
rb_enumeratorize_with_size(VALUE obj, VALUE meth, int argc, const VALUE *argv, rb_enumerator_size_func *size_fn)
{
/* Similar effect as calling obj.to_enum, i.e. dispatching to either
Kernel#to_enum vs Lazy#to_enum */
if (RTEST(rb_obj_is_kind_of(obj, rb_cLazy)))
return lazy_to_enum_i(obj, meth, argc, argv, size_fn, PASS_KW_SPLAT);
else
return enumerator_init(enumerator_allocate(rb_cEnumerator),
obj, meth, argc, argv, size_fn, Qnil, PASS_KW_SPLAT);
}
VALUE
rb_enumeratorize_with_size_kw(VALUE obj, VALUE meth, int argc, const VALUE *argv, rb_enumerator_size_func *size_fn, int kw_splat)
{
/* Similar effect as calling obj.to_enum, i.e. dispatching to either
Kernel#to_enum vs Lazy#to_enum */
if (RTEST(rb_obj_is_kind_of(obj, rb_cLazy)))
return lazy_to_enum_i(obj, meth, argc, argv, size_fn, kw_splat);
else
return enumerator_init(enumerator_allocate(rb_cEnumerator),
obj, meth, argc, argv, size_fn, Qnil, kw_splat);
}
static VALUE
enumerator_block_call(VALUE obj, rb_block_call_func *func, VALUE arg)
{
int argc = 0;
const VALUE *argv = 0;
const struct enumerator *e = enumerator_ptr(obj);
ID meth = e->meth;
if (e->args) {
argc = RARRAY_LENINT(e->args);
argv = RARRAY_CONST_PTR(e->args);
}
return rb_block_call_kw(e->obj, meth, argc, argv, func, arg, e->kw_splat);
}
/*
* call-seq:
* enum.each { |elm| block } -> obj
* enum.each -> enum
* enum.each(*appending_args) { |elm| block } -> obj
* enum.each(*appending_args) -> an_enumerator
*
* Iterates over the block according to how this Enumerator was constructed.
* If no block and no arguments are given, returns self.
*
* === Examples
*
* "Hello, world!".scan(/\w+/) #=> ["Hello", "world"]
* "Hello, world!".to_enum(:scan, /\w+/).to_a #=> ["Hello", "world"]
* "Hello, world!".to_enum(:scan).each(/\w+/).to_a #=> ["Hello", "world"]
*
* obj = Object.new
*
* def obj.each_arg(a, b=:b, *rest)
* yield a
* yield b
* yield rest
* :method_returned
* end
*
* enum = obj.to_enum :each_arg, :a, :x
*
* enum.each.to_a #=> [:a, :x, []]
* enum.each.equal?(enum) #=> true
* enum.each { |elm| elm } #=> :method_returned
*
* enum.each(:y, :z).to_a #=> [:a, :x, [:y, :z]]
* enum.each(:y, :z).equal?(enum) #=> false
* enum.each(:y, :z) { |elm| elm } #=> :method_returned
*
*/
static VALUE
enumerator_each(int argc, VALUE *argv, VALUE obj)
{
if (argc > 0) {
struct enumerator *e = enumerator_ptr(obj = rb_obj_dup(obj));
VALUE args = e->args;
if (args) {
#if SIZEOF_INT < SIZEOF_LONG
/* check int range overflow */
rb_long2int(RARRAY_LEN(args) + argc);
#endif
args = rb_ary_dup(args);
rb_ary_cat(args, argv, argc);
}
else {
args = rb_ary_new4(argc, argv);
}
e->args = args;
e->size = Qnil;
e->size_fn = 0;
}
if (!rb_block_given_p()) return obj;
return enumerator_block_call(obj, 0, obj);
}
static VALUE
enumerator_with_index_i(RB_BLOCK_CALL_FUNC_ARGLIST(val, m))
{
struct MEMO *memo = (struct MEMO *)m;
VALUE idx = memo->v1;
MEMO_V1_SET(memo, rb_int_succ(idx));
if (argc <= 1)
return rb_yield_values(2, val, idx);
return rb_yield_values(2, rb_ary_new4(argc, argv), idx);
}
static VALUE
enumerator_size(VALUE obj);
static VALUE
enumerator_enum_size(VALUE obj, VALUE args, VALUE eobj)
{
return enumerator_size(obj);
}
/*
* call-seq:
* e.with_index(offset = 0) {|(*args), idx| ... }
* e.with_index(offset = 0)
*
* Iterates the given block for each element with an index, which
* starts from +offset+. If no block is given, returns a new Enumerator
* that includes the index, starting from +offset+
*
* +offset+:: the starting index to use
*
*/
static VALUE
enumerator_with_index(int argc, VALUE *argv, VALUE obj)
{
VALUE memo;
rb_check_arity(argc, 0, 1);
RETURN_SIZED_ENUMERATOR(obj, argc, argv, enumerator_enum_size);
memo = (!argc || NIL_P(memo = argv[0])) ? INT2FIX(0) : rb_to_int(memo);
return enumerator_block_call(obj, enumerator_with_index_i, (VALUE)MEMO_NEW(memo, 0, 0));
}
/*
* call-seq:
* e.each_with_index {|(*args), idx| ... }
* e.each_with_index
*
* Same as Enumerator#with_index(0), i.e. there is no starting offset.
*
* If no block is given, a new Enumerator is returned that includes the index.
*
*/
static VALUE
enumerator_each_with_index(VALUE obj)
{
return enumerator_with_index(0, NULL, obj);
}
static VALUE
enumerator_with_object_i(RB_BLOCK_CALL_FUNC_ARGLIST(val, memo))
{
if (argc <= 1)
return rb_yield_values(2, val, memo);
return rb_yield_values(2, rb_ary_new4(argc, argv), memo);
}
/*
* call-seq:
* e.each_with_object(obj) {|(*args), obj| ... }
* e.each_with_object(obj)
* e.with_object(obj) {|(*args), obj| ... }
* e.with_object(obj)
*
* Iterates the given block for each element with an arbitrary object, +obj+,
* and returns +obj+
*
* If no block is given, returns a new Enumerator.
*
* === Example
*
* to_three = Enumerator.new do |y|
* 3.times do |x|
* y << x
* end
* end
*
* to_three_with_string = to_three.with_object("foo")
* to_three_with_string.each do |x,string|
* puts "#{string}: #{x}"
* end
*
* # => foo:0
* # => foo:1
* # => foo:2
*/
static VALUE
enumerator_with_object(VALUE obj, VALUE memo)
{
RETURN_SIZED_ENUMERATOR(obj, 1, &memo, enumerator_enum_size);
enumerator_block_call(obj, enumerator_with_object_i, memo);
return memo;
}
static VALUE
next_ii(RB_BLOCK_CALL_FUNC_ARGLIST(i, obj))
{
struct enumerator *e = enumerator_ptr(obj);
VALUE feedvalue = Qnil;
VALUE args = rb_ary_new4(argc, argv);
rb_fiber_yield(1, &args);
if (e->feedvalue != Qundef) {
feedvalue = e->feedvalue;
e->feedvalue = Qundef;
}
return feedvalue;
}
static VALUE
next_i(RB_BLOCK_CALL_FUNC_ARGLIST(_, obj))
{
struct enumerator *e = enumerator_ptr(obj);
VALUE nil = Qnil;
VALUE result;
result = rb_block_call(obj, id_each, 0, 0, next_ii, obj);
e->stop_exc = rb_exc_new2(rb_eStopIteration, "iteration reached an end");
rb_ivar_set(e->stop_exc, id_result, result);
return rb_fiber_yield(1, &nil);
}
static void
next_init(VALUE obj, struct enumerator *e)
{
VALUE curr = rb_fiber_current();
e->dst = curr;
e->fib = rb_fiber_new(next_i, obj);
e->lookahead = Qundef;
}
static VALUE
get_next_values(VALUE obj, struct enumerator *e)
{
VALUE curr, vs;
if (e->stop_exc)
rb_exc_raise(e->stop_exc);
curr = rb_fiber_current();
if (!e->fib || !rb_fiber_alive_p(e->fib)) {
next_init(obj, e);
}
vs = rb_fiber_resume(e->fib, 1, &curr);
if (e->stop_exc) {
e->fib = 0;
e->dst = Qnil;
e->lookahead = Qundef;
e->feedvalue = Qundef;
rb_exc_raise(e->stop_exc);
}
return vs;
}
/*
* call-seq:
* e.next_values -> array
*
* Returns the next object as an array in the enumerator, and move the
* internal position forward. When the position reached at the end,
* StopIteration is raised.
*
* This method can be used to distinguish <code>yield</code> and <code>yield
* nil</code>.
*
* === Example
*
* o = Object.new
* def o.each
* yield
* yield 1
* yield 1, 2
* yield nil
* yield [1, 2]
* end
* e = o.to_enum
* p e.next_values
* p e.next_values
* p e.next_values
* p e.next_values
* p e.next_values
* e = o.to_enum
* p e.next
* p e.next
* p e.next
* p e.next
* p e.next
*
* ## yield args next_values next
* # yield [] nil
* # yield 1 [1] 1
* # yield 1, 2 [1, 2] [1, 2]
* # yield nil [nil] nil
* # yield [1, 2] [[1, 2]] [1, 2]
*
* Note that +next_values+ does not affect other non-external enumeration
* methods unless underlying iteration method itself has side-effect, e.g.
* IO#each_line.
*
*/
static VALUE
enumerator_next_values(VALUE obj)
{
struct enumerator *e = enumerator_ptr(obj);
VALUE vs;
if (e->lookahead != Qundef) {
vs = e->lookahead;
e->lookahead = Qundef;
return vs;
}
return get_next_values(obj, e);
}
static VALUE
ary2sv(VALUE args, int dup)
{
if (!RB_TYPE_P(args, T_ARRAY))
return args;
switch (RARRAY_LEN(args)) {
case 0:
return Qnil;
case 1:
return RARRAY_AREF(args, 0);
default:
if (dup)
return rb_ary_dup(args);
return args;
}
}
/*
* call-seq:
* e.next -> object
*
* Returns the next object in the enumerator, and move the internal position
* forward. When the position reached at the end, StopIteration is raised.
*
* === Example
*
* a = [1,2,3]
* e = a.to_enum
* p e.next #=> 1
* p e.next #=> 2
* p e.next #=> 3
* p e.next #raises StopIteration
*
* Note that enumeration sequence by +next+ does not affect other non-external
* enumeration methods, unless the underlying iteration methods itself has
* side-effect, e.g. IO#each_line.
*
*/
static VALUE
enumerator_next(VALUE obj)
{
VALUE vs = enumerator_next_values(obj);
return ary2sv(vs, 0);
}
static VALUE
enumerator_peek_values(VALUE obj)
{
struct enumerator *e = enumerator_ptr(obj);
if (e->lookahead == Qundef) {
e->lookahead = get_next_values(obj, e);
}
return e->lookahead;
}
/*
* call-seq:
* e.peek_values -> array
*
* Returns the next object as an array, similar to Enumerator#next_values, but
* doesn't move the internal position forward. If the position is already at
* the end, StopIteration is raised.
*
* === Example
*
* o = Object.new
* def o.each
* yield
* yield 1
* yield 1, 2
* end
* e = o.to_enum
* p e.peek_values #=> []
* e.next
* p e.peek_values #=> [1]
* p e.peek_values #=> [1]
* e.next
* p e.peek_values #=> [1, 2]
* e.next
* p e.peek_values # raises StopIteration
*
*/
static VALUE
enumerator_peek_values_m(VALUE obj)
{
return rb_ary_dup(enumerator_peek_values(obj));
}
/*
* call-seq:
* e.peek -> object
*
* Returns the next object in the enumerator, but doesn't move the internal
* position forward. If the position is already at the end, StopIteration
* is raised.
*
* === Example
*
* a = [1,2,3]
* e = a.to_enum
* p e.next #=> 1
* p e.peek #=> 2
* p e.peek #=> 2
* p e.peek #=> 2
* p e.next #=> 2
* p e.next #=> 3
* p e.peek #raises StopIteration
*
*/
static VALUE
enumerator_peek(VALUE obj)
{
VALUE vs = enumerator_peek_values(obj);
return ary2sv(vs, 1);
}
/*
* call-seq:
* e.feed obj -> nil
*
* Sets the value to be returned by the next yield inside +e+.
*
* If the value is not set, the yield returns nil.
*
* This value is cleared after being yielded.
*
* # Array#map passes the array's elements to "yield" and collects the
* # results of "yield" as an array.
* # Following example shows that "next" returns the passed elements and
* # values passed to "feed" are collected as an array which can be
* # obtained by StopIteration#result.
* e = [1,2,3].map
* p e.next #=> 1
* e.feed "a"
* p e.next #=> 2
* e.feed "b"
* p e.next #=> 3
* e.feed "c"
* begin
* e.next
* rescue StopIteration
* p $!.result #=> ["a", "b", "c"]
* end
*
* o = Object.new
* def o.each
* x = yield # (2) blocks
* p x # (5) => "foo"
* x = yield # (6) blocks
* p x # (8) => nil
* x = yield # (9) blocks
* p x # not reached w/o another e.next
* end
*
* e = o.to_enum
* e.next # (1)
* e.feed "foo" # (3)
* e.next # (4)
* e.next # (7)
* # (10)
*/
static VALUE
enumerator_feed(VALUE obj, VALUE v)
{
struct enumerator *e = enumerator_ptr(obj);
if (e->feedvalue != Qundef) {
rb_raise(rb_eTypeError, "feed value already set");
}
e->feedvalue = v;
return Qnil;
}
/*
* call-seq:
* e.rewind -> e
*
* Rewinds the enumeration sequence to the beginning.
*
* If the enclosed object responds to a "rewind" method, it is called.
*/
static VALUE
enumerator_rewind(VALUE obj)
{
struct enumerator *e = enumerator_ptr(obj);
rb_check_funcall(e->obj, id_rewind, 0, 0);
e->fib = 0;
e->dst = Qnil;
e->lookahead = Qundef;
e->feedvalue = Qundef;
e->stop_exc = Qfalse;
return obj;
}
static struct generator *generator_ptr(VALUE obj);
static VALUE append_method(VALUE obj, VALUE str, ID default_method, VALUE default_args);
static VALUE
inspect_enumerator(VALUE obj, VALUE dummy, int recur)
{
struct enumerator *e;
VALUE eobj, str, cname;
TypedData_Get_Struct(obj, struct enumerator, &enumerator_data_type, e);
cname = rb_obj_class(obj);
if (!e || e->obj == Qundef) {
return rb_sprintf("#<%"PRIsVALUE": uninitialized>", rb_class_path(cname));
}
if (recur) {
str = rb_sprintf("#<%"PRIsVALUE": ...>", rb_class_path(cname));
return str;
}
if (e->procs) {
long i;
eobj = generator_ptr(e->obj)->obj;
/* In case procs chained enumerator traversing all proc entries manually */
if (rb_obj_class(eobj) == cname) {
str = rb_inspect(eobj);
}
else {
str = rb_sprintf("#<%"PRIsVALUE": %+"PRIsVALUE">", rb_class_path(cname), eobj);
}
for (i = 0; i < RARRAY_LEN(e->procs); i++) {
str = rb_sprintf("#<%"PRIsVALUE": %"PRIsVALUE, cname, str);
append_method(RARRAY_AREF(e->procs, i), str, e->meth, e->args);
rb_str_buf_cat2(str, ">");
}
return str;
}
eobj = rb_attr_get(obj, id_receiver);
if (NIL_P(eobj)) {
eobj = e->obj;
}
/* (1..100).each_cons(2) => "#<Enumerator: 1..100:each_cons(2)>" */
str = rb_sprintf("#<%"PRIsVALUE": %+"PRIsVALUE, rb_class_path(cname), eobj);
append_method(obj, str, e->meth, e->args);
rb_str_buf_cat2(str, ">");
return str;
}
static int
key_symbol_p(VALUE key, VALUE val, VALUE arg)
{
if (SYMBOL_P(key)) return ST_CONTINUE;
*(int *)arg = FALSE;
return ST_STOP;
}
static int
kwd_append(VALUE key, VALUE val, VALUE str)
{
if (!SYMBOL_P(key)) rb_raise(rb_eRuntimeError, "non-symbol key inserted");
rb_str_catf(str, "% "PRIsVALUE": %"PRIsVALUE", ", key, val);
return ST_CONTINUE;
}
static VALUE
append_method(VALUE obj, VALUE str, ID default_method, VALUE default_args)
{
VALUE method, eargs;
method = rb_attr_get(obj, id_method);
if (method != Qfalse) {
if (!NIL_P(method)) {
Check_Type(method, T_SYMBOL);
method = rb_sym2str(method);
}
else {
method = rb_id2str(default_method);
}
rb_str_buf_cat2(str, ":");
rb_str_buf_append(str, method);
}
eargs = rb_attr_get(obj, id_arguments);
if (NIL_P(eargs)) {
eargs = default_args;
}
if (eargs != Qfalse) {
long argc = RARRAY_LEN(eargs);
const VALUE *argv = RARRAY_CONST_PTR(eargs); /* WB: no new reference */
if (argc > 0) {
VALUE kwds = Qnil;
rb_str_buf_cat2(str, "(");
if (RB_TYPE_P(argv[argc-1], T_HASH) && !RHASH_EMPTY_P(argv[argc-1])) {
int all_key = TRUE;
rb_hash_foreach(argv[argc-1], key_symbol_p, (VALUE)&all_key);
if (all_key) kwds = argv[--argc];
}
while (argc--) {
VALUE arg = *argv++;
rb_str_append(str, rb_inspect(arg));
rb_str_buf_cat2(str, ", ");
}
if (!NIL_P(kwds)) {
rb_hash_foreach(kwds, kwd_append, str);
}
rb_str_set_len(str, RSTRING_LEN(str)-2);
rb_str_buf_cat2(str, ")");
}
}
return str;
}
/*
* call-seq:
* e.inspect -> string
*
* Creates a printable version of <i>e</i>.
*/
static VALUE
enumerator_inspect(VALUE obj)
{
return rb_exec_recursive(inspect_enumerator, obj, 0);
}
/*
* call-seq:
* e.size -> int, Float::INFINITY or nil
*
* Returns the size of the enumerator, or +nil+ if it can't be calculated lazily.
*
* (1..100).to_a.permutation(4).size # => 94109400
* loop.size # => Float::INFINITY
* (1..100).drop_while.size # => nil
*/
static VALUE
enumerator_size(VALUE obj)
{
struct enumerator *e = enumerator_ptr(obj);
int argc = 0;
const VALUE *argv = NULL;
VALUE size;
if (e->procs) {
struct generator *g = generator_ptr(e->obj);
VALUE receiver = rb_check_funcall(g->obj, id_size, 0, 0);
long i = 0;
for (i = 0; i < RARRAY_LEN(e->procs); i++) {
VALUE proc = RARRAY_AREF(e->procs, i);
struct proc_entry *entry = proc_entry_ptr(proc);
lazyenum_size_func *size_fn = entry->fn->size;
if (!size_fn) {
return Qnil;
}
receiver = (*size_fn)(proc, receiver);
}
return receiver;
}
if (e->size_fn) {
return (*e->size_fn)(e->obj, e->args, obj);
}
if (e->args) {
argc = (int)RARRAY_LEN(e->args);
argv = RARRAY_CONST_PTR(e->args);
}
size = rb_check_funcall_kw(e->size, id_call, argc, argv, e->kw_splat);
if (size != Qundef) return size;
return e->size;
}
/*
* Yielder
*/
static void
yielder_mark(void *p)
{
struct yielder *ptr = p;
rb_gc_mark_movable(ptr->proc);
}
static void
yielder_compact(void *p)
{
struct yielder *ptr = p;
ptr->proc = rb_gc_location(ptr->proc);
}
#define yielder_free RUBY_TYPED_DEFAULT_FREE
static size_t
yielder_memsize(const void *p)
{
return sizeof(struct yielder);
}
static const rb_data_type_t yielder_data_type = {
"yielder",
{
yielder_mark,
yielder_free,
yielder_memsize,
yielder_compact,
},
0, 0, RUBY_TYPED_FREE_IMMEDIATELY
};
static struct yielder *
yielder_ptr(VALUE obj)
{
struct yielder *ptr;
TypedData_Get_Struct(obj, struct yielder, &yielder_data_type, ptr);
if (!ptr || ptr->proc == Qundef) {
rb_raise(rb_eArgError, "uninitialized yielder");
}
return ptr;
}
/* :nodoc: */
static VALUE
yielder_allocate(VALUE klass)
{
struct yielder *ptr;
VALUE obj;
obj = TypedData_Make_Struct(klass, struct yielder, &yielder_data_type, ptr);
ptr->proc = Qundef;
return obj;
}
static VALUE
yielder_init(VALUE obj, VALUE proc)
{
struct yielder *ptr;
TypedData_Get_Struct(obj, struct yielder, &yielder_data_type, ptr);
if (!ptr) {
rb_raise(rb_eArgError, "unallocated yielder");
}
ptr->proc = proc;
return obj;
}
/* :nodoc: */
static VALUE
yielder_initialize(VALUE obj)
{
rb_need_block();
return yielder_init(obj, rb_block_proc());
}
/* :nodoc: */
static VALUE
yielder_yield(VALUE obj, VALUE args)
{
struct yielder *ptr = yielder_ptr(obj);
return rb_proc_call_kw(ptr->proc, args, RB_PASS_CALLED_KEYWORDS);
}
/* :nodoc: */
static VALUE
yielder_yield_push(VALUE obj, VALUE arg)
{
struct yielder *ptr = yielder_ptr(obj);
rb_proc_call_with_block(ptr->proc, 1, &arg, Qnil);
return obj;
}
/*
* Returns a Proc object that takes an argument and yields it.
*
* This method is implemented so that a Yielder object can be directly
* passed to another method as a block argument.
*
* enum = Enumerator.new { |y|
* Dir.glob("*.rb") { |file|
* File.open(file) { |f| f.each_line(&y) }
* }
* }
*/
static VALUE
yielder_to_proc(VALUE obj)
{
VALUE method = rb_obj_method(obj, sym_yield);
return rb_funcall(method, idTo_proc, 0);
}
static VALUE
yielder_yield_i(RB_BLOCK_CALL_FUNC_ARGLIST(obj, memo))
{
return rb_yield_values_kw(argc, argv, RB_PASS_CALLED_KEYWORDS);
}
static VALUE
yielder_new(void)
{
return yielder_init(yielder_allocate(rb_cYielder), rb_proc_new(yielder_yield_i, 0));
}
/*
* Generator
*/
static void
generator_mark(void *p)
{
struct generator *ptr = p;
rb_gc_mark_movable(ptr->proc);
rb_gc_mark_movable(ptr->obj);
}
static void
generator_compact(void *p)
{
struct generator *ptr = p;
ptr->proc = rb_gc_location(ptr->proc);
ptr->obj = rb_gc_location(ptr->obj);
}
#define generator_free RUBY_TYPED_DEFAULT_FREE
static size_t
generator_memsize(const void *p)
{
return sizeof(struct generator);
}
static const rb_data_type_t generator_data_type = {
"generator",
{
generator_mark,
generator_free,
generator_memsize,
generator_compact,
},
0, 0, RUBY_TYPED_FREE_IMMEDIATELY
};
static struct generator *
generator_ptr(VALUE obj)
{
struct generator *ptr;
TypedData_Get_Struct(obj, struct generator, &generator_data_type, ptr);
if (!ptr || ptr->proc == Qundef) {
rb_raise(rb_eArgError, "uninitialized generator");
}
return ptr;
}
/* :nodoc: */
static VALUE
generator_allocate(VALUE klass)
{
struct generator *ptr;
VALUE obj;
obj = TypedData_Make_Struct(klass, struct generator, &generator_data_type, ptr);
ptr->proc = Qundef;
return obj;
}
static VALUE
generator_init(VALUE obj, VALUE proc)
{
struct generator *ptr;
rb_check_frozen(obj);
TypedData_Get_Struct(obj, struct generator, &generator_data_type, ptr);
if (!ptr) {
rb_raise(rb_eArgError, "unallocated generator");
}
ptr->proc = proc;
return obj;
}
/* :nodoc: */
static VALUE
generator_initialize(int argc, VALUE *argv, VALUE obj)
{
VALUE proc;
if (argc == 0) {
rb_need_block();
proc = rb_block_proc();
}
else {
rb_scan_args(argc, argv, "1", &proc);
if (!rb_obj_is_proc(proc))
rb_raise(rb_eTypeError,
"wrong argument type %"PRIsVALUE" (expected Proc)",
rb_obj_class(proc));
if (rb_block_given_p()) {
rb_warn("given block not used");
}
}
return generator_init(obj, proc);
}
/* :nodoc: */
static VALUE
generator_init_copy(VALUE obj, VALUE orig)
{
struct generator *ptr0, *ptr1;
if (!OBJ_INIT_COPY(obj, orig)) return obj;
ptr0 = generator_ptr(orig);
TypedData_Get_Struct(obj, struct generator, &generator_data_type, ptr1);
if (!ptr1) {
rb_raise(rb_eArgError, "unallocated generator");
}
ptr1->proc = ptr0->proc;
return obj;
}
/* :nodoc: */
static VALUE
generator_each(int argc, VALUE *argv, VALUE obj)
{
struct generator *ptr = generator_ptr(obj);
VALUE args = rb_ary_new2(argc + 1);
rb_ary_push(args, yielder_new());
if (argc > 0) {
rb_ary_cat(args, argv, argc);
}
return rb_proc_call_kw(ptr->proc, args, RB_PASS_CALLED_KEYWORDS);
}
/* Lazy Enumerator methods */
static VALUE
enum_size(VALUE self)
{
VALUE r = rb_check_funcall(self, id_size, 0, 0);
return (r == Qundef) ? Qnil : r;
}
static VALUE
lazyenum_size(VALUE self, VALUE args, VALUE eobj)
{
return enum_size(self);
}
static VALUE
lazy_size(VALUE self)
{
return enum_size(rb_ivar_get(self, id_receiver));
}
static VALUE
lazy_receiver_size(VALUE generator, VALUE args, VALUE lazy)
{
return lazy_size(lazy);
}
static VALUE
lazy_init_iterator(RB_BLOCK_CALL_FUNC_ARGLIST(val, m))
{
VALUE result;
if (argc == 1) {
VALUE args[2];
args[0] = m;
args[1] = val;
result = rb_yield_values2(2, args);
}
else {
VALUE args;
int len = rb_long2int((long)argc + 1);
VALUE *nargv = ALLOCV_N(VALUE, args, len);
nargv[0] = m;
if (argc > 0) {
MEMCPY(nargv + 1, argv, VALUE, argc);
}
result = rb_yield_values2(len, nargv);
ALLOCV_END(args);
}
if (result == Qundef) rb_iter_break();
return Qnil;
}
static VALUE
lazy_init_block_i(RB_BLOCK_CALL_FUNC_ARGLIST(val, m))
{
rb_block_call(m, id_each, argc-1, argv+1, lazy_init_iterator, val);
return Qnil;
}
#define memo_value v2
#define memo_flags u3.state
#define LAZY_MEMO_BREAK 1
#define LAZY_MEMO_PACKED 2
#define LAZY_MEMO_BREAK_P(memo) ((memo)->memo_flags & LAZY_MEMO_BREAK)
#define LAZY_MEMO_PACKED_P(memo) ((memo)->memo_flags & LAZY_MEMO_PACKED)
#define LAZY_MEMO_SET_BREAK(memo) ((memo)->memo_flags |= LAZY_MEMO_BREAK)
#define LAZY_MEMO_SET_VALUE(memo, value) MEMO_V2_SET(memo, value)
#define LAZY_MEMO_SET_PACKED(memo) ((memo)->memo_flags |= LAZY_MEMO_PACKED)
#define LAZY_MEMO_RESET_PACKED(memo) ((memo)->memo_flags &= ~LAZY_MEMO_PACKED)
static VALUE
lazy_init_yielder(RB_BLOCK_CALL_FUNC_ARGLIST(_, m))
{
VALUE yielder = RARRAY_AREF(m, 0);
VALUE procs_array = RARRAY_AREF(m, 1);
VALUE memos = rb_attr_get(yielder, id_memo);
long i = 0;
struct MEMO *result;
int cont = 1;
result = MEMO_NEW(Qnil, rb_enum_values_pack(argc, argv),
argc > 1 ? LAZY_MEMO_PACKED : 0);
for (i = 0; i < RARRAY_LEN(procs_array); i++) {
VALUE proc = RARRAY_AREF(procs_array, i);
struct proc_entry *entry = proc_entry_ptr(proc);
if (!(*entry->fn->proc)(proc, result, memos, i)) {
cont = 0;
break;
}
}
if (cont) {
rb_funcall2(yielder, idLTLT, 1, &(result->memo_value));
}
if (LAZY_MEMO_BREAK_P(result)) {
rb_iter_break();
}
return result->memo_value;
}
static VALUE
lazy_init_block(RB_BLOCK_CALL_FUNC_ARGLIST(val, m))
{
VALUE procs = RARRAY_AREF(m, 1);
rb_ivar_set(val, id_memo, rb_ary_new2(RARRAY_LEN(procs)));
rb_block_call(RARRAY_AREF(m, 0), id_each, 0, 0,
lazy_init_yielder, rb_ary_new3(2, val, procs));
return Qnil;
}
static VALUE
lazy_generator_init(VALUE enumerator, VALUE procs)
{
VALUE generator;
VALUE obj;
struct generator *gen_ptr;
struct enumerator *e = enumerator_ptr(enumerator);
if (RARRAY_LEN(procs) > 0) {
struct generator *old_gen_ptr = generator_ptr(e->obj);
obj = old_gen_ptr->obj;
}
else {
obj = enumerator;
}
generator = generator_allocate(rb_cGenerator);
rb_block_call(generator, id_initialize, 0, 0,
lazy_init_block, rb_ary_new3(2, obj, procs));
gen_ptr = generator_ptr(generator);
gen_ptr->obj = obj;
return generator;
}
/*
* Document-class: Enumerator::Lazy
*
* Enumerator::Lazy is a special type of Enumerator, that allows constructing
* chains of operations without evaluating them immediately, and evaluating
* values on as-needed basis. In order to do so it redefines most of Enumerable
* methods so that they just construct another lazy enumerator.
*
* Enumerator::Lazy can be constructed from any Enumerable with the
* Enumerable#lazy method.
*
* lazy = (1..Float::INFINITY).lazy.select(&:odd?).drop(10).take_while { |i| i < 30 }
* # => #<Enumerator::Lazy: #<Enumerator::Lazy: #<Enumerator::Lazy: #<Enumerator::Lazy: 1..Infinity>:select>:drop(10)>:take_while>
*
* The real enumeration is performed when any non-redefined Enumerable method
* is called, like Enumerable#first or Enumerable#to_a (the latter is aliased
* as #force for more semantic code):
*
* lazy.first(2)
* #=> [21, 23]
*
* lazy.force
* #=> [21, 23, 25, 27, 29]
*
* Note that most Enumerable methods that could be called with or without
* a block, on Enumerator::Lazy will always require a block:
*
* [1, 2, 3].map #=> #<Enumerator: [1, 2, 3]:map>
* [1, 2, 3].lazy.map # ArgumentError: tried to call lazy map without a block
*
* This class allows idiomatic calculations on long or infinite sequences, as well
* as chaining of calculations without constructing intermediate arrays.
*
* Example for working with a slowly calculated sequence:
*
* require 'open-uri'
*
* # This will fetch all URLs before selecting
* # necessary data
* URLS.map { |u| JSON.parse(open(u).read) }
* .select { |data| data.key?('stats') }
* .first(5)
*
* # This will fetch URLs one-by-one, only till
* # there is enough data to satisfy the condition
* URLS.lazy.map { |u| JSON.parse(open(u).read) }
* .select { |data| data.key?('stats') }
* .first(5)
*
* Ending a chain with ".eager" generates a non-lazy enumerator, which
* is suitable for returning or passing to another method that expects
* a normal enumerator.
*
* def active_items
* groups
* .lazy
* .flat_map(&:items)
* .reject(&:disabled)
* .eager
* end
*
* # This works lazily; if a checked item is found, it stops
* # iteration and does not look into remaining groups.
* first_checked = active_items.find(&:checked)
*
* # This returns an array of items like a normal enumerator does.
* all_checked = active_items.select(&:checked)
*
*/
/*
* call-seq:
* Lazy.new(obj, size=nil) { |yielder, *values| ... }
*
* Creates a new Lazy enumerator. When the enumerator is actually enumerated
* (e.g. by calling #force), +obj+ will be enumerated and each value passed
* to the given block. The block can yield values back using +yielder+.
* For example, to create a "filter+map" enumerator:
*
* def filter_map(sequence)
* Lazy.new(sequence) do |yielder, *values|
* result = yield *values
* yielder << result if result
* end
* end
*
* filter_map(1..Float::INFINITY) {|i| i*i if i.even?}.first(5)
* #=> [4, 16, 36, 64, 100]
*/
static VALUE
lazy_initialize(int argc, VALUE *argv, VALUE self)
{
VALUE obj, size = Qnil;
VALUE generator;
rb_check_arity(argc, 1, 2);
if (!rb_block_given_p()) {
rb_raise(rb_eArgError, "tried to call lazy new without a block");
}
obj = argv[0];
if (argc > 1) {
size = argv[1];
}
generator = generator_allocate(rb_cGenerator);
rb_block_call(generator, id_initialize, 0, 0, lazy_init_block_i, obj);
enumerator_init(self, generator, sym_each, 0, 0, 0, size, 0);
rb_ivar_set(self, id_receiver, obj);
return self;
}
#if 0 /* for RDoc */
/*
* call-seq:
* lazy.to_a -> array
* lazy.force -> array
*
* Expands +lazy+ enumerator to an array.
* See Enumerable#to_a.
*/
static VALUE lazy_to_a(VALUE self)
{
}
#endif
static void
lazy_set_args(VALUE lazy, VALUE args)
{
ID id = rb_frame_this_func();
rb_ivar_set(lazy, id_method, ID2SYM(id));
if (NIL_P(args)) {
/* Qfalse indicates that the arguments are empty */
rb_ivar_set(lazy, id_arguments, Qfalse);
}
else {
rb_ivar_set(lazy, id_arguments, args);
}
}
static VALUE
lazy_set_method(VALUE lazy, VALUE args, rb_enumerator_size_func *size_fn)
{
struct enumerator *e = enumerator_ptr(lazy);
lazy_set_args(lazy, args);
e->size_fn = size_fn;
return lazy;
}
static VALUE
lazy_add_method(VALUE obj, int argc, VALUE *argv, VALUE args, VALUE memo,
const lazyenum_funcs *fn)
{
struct enumerator *new_e;
VALUE new_obj;
VALUE new_generator;
VALUE new_procs;
struct enumerator *e = enumerator_ptr(obj);
struct proc_entry *entry;
VALUE entry_obj = TypedData_Make_Struct(rb_cObject, struct proc_entry,
&proc_entry_data_type, entry);
if (rb_block_given_p()) {
entry->proc = rb_block_proc();
}
entry->fn = fn;
entry->memo = args;
lazy_set_args(entry_obj, memo);
new_procs = RTEST(e->procs) ? rb_ary_dup(e->procs) : rb_ary_new();
new_generator = lazy_generator_init(obj, new_procs);
rb_ary_push(new_procs, entry_obj);
new_obj = enumerator_init_copy(enumerator_allocate(rb_cLazy), obj);
new_e = DATA_PTR(new_obj);
new_e->obj = new_generator;
new_e->procs = new_procs;
if (argc > 0) {
new_e->meth = rb_to_id(*argv++);
--argc;
}
else {
new_e->meth = id_each;
}
new_e->args = rb_ary_new4(argc, argv);
return new_obj;
}
/*
* call-seq:
* e.lazy -> lazy_enumerator
*
* Returns an Enumerator::Lazy, which redefines most Enumerable
* methods to postpone enumeration and enumerate values only on an
* as-needed basis.
*
* === Example
*
* The following program finds pythagorean triples:
*
* def pythagorean_triples
* (1..Float::INFINITY).lazy.flat_map {|z|
* (1..z).flat_map {|x|
* (x..z).select {|y|
* x**2 + y**2 == z**2
* }.map {|y|
* [x, y, z]
* }
* }
* }
* end
* # show first ten pythagorean triples
* p pythagorean_triples.take(10).force # take is lazy, so force is needed
* p pythagorean_triples.first(10) # first is eager
* # show pythagorean triples less than 100
* p pythagorean_triples.take_while { |*, z| z < 100 }.force
*/
static VALUE
enumerable_lazy(VALUE obj)
{
VALUE result = lazy_to_enum_i(obj, sym_each, 0, 0, lazyenum_size, PASS_KW_SPLAT);
/* Qfalse indicates that the Enumerator::Lazy has no method name */
rb_ivar_set(result, id_method, Qfalse);
return result;
}
static VALUE
lazy_to_enum_i(VALUE obj, VALUE meth, int argc, const VALUE *argv, rb_enumerator_size_func *size_fn, int kw_splat)
{
return enumerator_init(enumerator_allocate(rb_cLazy),
obj, meth, argc, argv, size_fn, Qnil, kw_splat);
}
/*
* call-seq:
* lzy.to_enum(method = :each, *args) -> lazy_enum
* lzy.enum_for(method = :each, *args) -> lazy_enum
* lzy.to_enum(method = :each, *args) {|*args| block} -> lazy_enum
* lzy.enum_for(method = :each, *args){|*args| block} -> lazy_enum
*
* Similar to Object#to_enum, except it returns a lazy enumerator.
* This makes it easy to define Enumerable methods that will
* naturally remain lazy if called from a lazy enumerator.
*
* For example, continuing from the example in Object#to_enum:
*
* # See Object#to_enum for the definition of repeat
* r = 1..Float::INFINITY
* r.repeat(2).first(5) # => [1, 1, 2, 2, 3]
* r.repeat(2).class # => Enumerator
* r.repeat(2).map{|n| n ** 2}.first(5) # => endless loop!
* # works naturally on lazy enumerator:
* r.lazy.repeat(2).class # => Enumerator::Lazy
* r.lazy.repeat(2).map{|n| n ** 2}.first(5) # => [1, 1, 4, 4, 9]
*/
static VALUE
lazy_to_enum(int argc, VALUE *argv, VALUE self)
{
VALUE lazy, meth = sym_each, super_meth;
if (argc > 0) {
--argc;
meth = *argv++;
}
if (RTEST((super_meth = rb_hash_aref(lazy_use_super_method, meth)))) {
meth = super_meth;
}
lazy = lazy_to_enum_i(self, meth, argc, argv, 0, PASS_KW_SPLAT);
if (rb_block_given_p()) {
enumerator_ptr(lazy)->size = rb_block_proc();
}
return lazy;
}
static VALUE
lazy_eager_size(VALUE self, VALUE args, VALUE eobj)
{
return enum_size(self);
}
/*
* call-seq:
* lzy.eager -> enum
*
* Returns a non-lazy Enumerator converted from the lazy enumerator.
*/
static VALUE
lazy_eager(VALUE self)
{
return enumerator_init(enumerator_allocate(rb_cEnumerator),
self, sym_each, 0, 0, lazy_eager_size, Qnil, 0);
}
static VALUE
lazyenum_yield(VALUE proc_entry, struct MEMO *result)
{
struct proc_entry *entry = proc_entry_ptr(proc_entry);
return rb_proc_call_with_block(entry->proc, 1, &result->memo_value, Qnil);
}
static VALUE
lazyenum_yield_values(VALUE proc_entry, struct MEMO *result)
{
struct proc_entry *entry = proc_entry_ptr(proc_entry);
int argc = 1;
const VALUE *argv = &result->memo_value;
if (LAZY_MEMO_PACKED_P(result)) {
const VALUE args = *argv;
argc = RARRAY_LENINT(args);
argv = RARRAY_CONST_PTR(args);
}
return rb_proc_call_with_block(entry->proc, argc, argv, Qnil);
}
static struct MEMO *
lazy_map_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_index)
{
VALUE value = lazyenum_yield_values(proc_entry, result);
LAZY_MEMO_SET_VALUE(result, value);
LAZY_MEMO_RESET_PACKED(result);
return result;
}
static VALUE
lazy_map_size(VALUE entry, VALUE receiver)
{
return receiver;
}
static const lazyenum_funcs lazy_map_funcs = {
lazy_map_proc, lazy_map_size,
};
/*
* call-seq:
* lazy.collect { |obj| block } -> lazy_enumerator
* lazy.map { |obj| block } -> lazy_enumerator
*
* Like Enumerable#map, but chains operation to be lazy-evaluated.
*
* (1..Float::INFINITY).lazy.map {|i| i**2 }
* #=> #<Enumerator::Lazy: #<Enumerator::Lazy: 1..Infinity>:map>
* (1..Float::INFINITY).lazy.map {|i| i**2 }.first(3)
* #=> [1, 4, 9]
*/
static VALUE
lazy_map(VALUE obj)
{
if (!rb_block_given_p()) {
rb_raise(rb_eArgError, "tried to call lazy map without a block");
}
return lazy_add_method(obj, 0, 0, Qnil, Qnil, &lazy_map_funcs);
}
static VALUE
lazy_flat_map_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, yielder))
{
VALUE arg = rb_enum_values_pack(argc, argv);
return rb_funcallv(yielder, idLTLT, 1, &arg);
}
static VALUE
lazy_flat_map_each(VALUE obj, VALUE yielder)
{
rb_block_call(obj, id_each, 0, 0, lazy_flat_map_i, yielder);
return Qnil;
}
static VALUE
lazy_flat_map_to_ary(VALUE obj, VALUE yielder)
{
VALUE ary = rb_check_array_type(obj);
if (NIL_P(ary)) {
rb_funcall(yielder, idLTLT, 1, obj);
}
else {
long i;
for (i = 0; i < RARRAY_LEN(ary); i++) {
rb_funcall(yielder, idLTLT, 1, RARRAY_AREF(ary, i));
}
}
return Qnil;
}
static VALUE
lazy_flat_map_proc(RB_BLOCK_CALL_FUNC_ARGLIST(val, m))
{
VALUE result = rb_yield_values2(argc - 1, &argv[1]);
if (RB_TYPE_P(result, T_ARRAY)) {
long i;
for (i = 0; i < RARRAY_LEN(result); i++) {
rb_funcall(argv[0], idLTLT, 1, RARRAY_AREF(result, i));
}
}
else {
if (rb_respond_to(result, id_force) && rb_respond_to(result, id_each)) {
lazy_flat_map_each(result, argv[0]);
}
else {
lazy_flat_map_to_ary(result, argv[0]);
}
}
return Qnil;
}
/*
* call-seq:
* lazy.collect_concat { |obj| block } -> a_lazy_enumerator
* lazy.flat_map { |obj| block } -> a_lazy_enumerator
*
* Returns a new lazy enumerator with the concatenated results of running
* <i>block</i> once for every element in <i>lazy</i>.
*
* ["foo", "bar"].lazy.flat_map {|i| i.each_char.lazy}.force
* #=> ["f", "o", "o", "b", "a", "r"]
*
* A value <i>x</i> returned by <i>block</i> is decomposed if either of
* the following conditions is true:
*
* * a) <i>x</i> responds to both each and force, which means that
* <i>x</i> is a lazy enumerator.
* * b) <i>x</i> is an array or responds to to_ary.
*
* Otherwise, <i>x</i> is contained as-is in the return value.
*
* [{a:1}, {b:2}].lazy.flat_map {|i| i}.force
* #=> [{:a=>1}, {:b=>2}]
*/
static VALUE
lazy_flat_map(VALUE obj)
{
if (!rb_block_given_p()) {
rb_raise(rb_eArgError, "tried to call lazy flat_map without a block");
}
return lazy_set_method(rb_block_call(rb_cLazy, id_new, 1, &obj,
lazy_flat_map_proc, 0),
Qnil, 0);
}
static struct MEMO *
lazy_select_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_index)
{
VALUE chain = lazyenum_yield(proc_entry, result);
if (!RTEST(chain)) return 0;
return result;
}
static const lazyenum_funcs lazy_select_funcs = {
lazy_select_proc, 0,
};
/*
* call-seq:
* lazy.find_all { |obj| block } -> lazy_enumerator
* lazy.select { |obj| block } -> lazy_enumerator
* lazy.filter { |obj| block } -> lazy_enumerator
*
* Like Enumerable#select, but chains operation to be lazy-evaluated.
*/
static VALUE
lazy_select(VALUE obj)
{
if (!rb_block_given_p()) {
rb_raise(rb_eArgError, "tried to call lazy select without a block");
}
return lazy_add_method(obj, 0, 0, Qnil, Qnil, &lazy_select_funcs);
}
static struct MEMO *
lazy_filter_map_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_index)
{
VALUE value = lazyenum_yield_values(proc_entry, result);
if (!RTEST(value)) return 0;
LAZY_MEMO_SET_VALUE(result, value);
LAZY_MEMO_RESET_PACKED(result);
return result;
}
static const lazyenum_funcs lazy_filter_map_funcs = {
lazy_filter_map_proc, 0,
};
/*
* call-seq:
* lazy.filter_map { |obj| block } -> lazy_enumerator
*
* Like Enumerable#filter_map, but chains operation to be lazy-evaluated.
*
* (1..).lazy.filter_map { |i| i * 2 if i.even? }.first(5) #=> [4, 8, 12, 16, 20]
*/
static VALUE
lazy_filter_map(VALUE obj)
{
if (!rb_block_given_p()) {
rb_raise(rb_eArgError, "tried to call lazy filter_map without a block");
}
return lazy_add_method(obj, 0, 0, Qnil, Qnil, &lazy_filter_map_funcs);
}
static struct MEMO *
lazy_reject_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_index)
{
VALUE chain = lazyenum_yield(proc_entry, result);
if (RTEST(chain)) return 0;
return result;
}
static const lazyenum_funcs lazy_reject_funcs = {
lazy_reject_proc, 0,
};
/*
* call-seq:
* lazy.reject { |obj| block } -> lazy_enumerator
*
* Like Enumerable#reject, but chains operation to be lazy-evaluated.
*/
static VALUE
lazy_reject(VALUE obj)
{
if (!rb_block_given_p()) {
rb_raise(rb_eArgError, "tried to call lazy reject without a block");
}
return lazy_add_method(obj, 0, 0, Qnil, Qnil, &lazy_reject_funcs);
}
static struct MEMO *
lazy_grep_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_index)
{
struct proc_entry *entry = proc_entry_ptr(proc_entry);
VALUE chain = rb_funcall(entry->memo, id_eqq, 1, result->memo_value);
if (!RTEST(chain)) return 0;
return result;
}
static struct MEMO *
lazy_grep_iter_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_index)
{
struct proc_entry *entry = proc_entry_ptr(proc_entry);
VALUE value, chain = rb_funcall(entry->memo, id_eqq, 1, result->memo_value);
if (!RTEST(chain)) return 0;
value = rb_proc_call_with_block(entry->proc, 1, &(result->memo_value), Qnil);
LAZY_MEMO_SET_VALUE(result, value);
LAZY_MEMO_RESET_PACKED(result);
return result;
}
static const lazyenum_funcs lazy_grep_iter_funcs = {
lazy_grep_iter_proc, 0,
};
static const lazyenum_funcs lazy_grep_funcs = {
lazy_grep_proc, 0,
};
/*
* call-seq:
* lazy.grep(pattern) -> lazy_enumerator
* lazy.grep(pattern) { |obj| block } -> lazy_enumerator
*
* Like Enumerable#grep, but chains operation to be lazy-evaluated.
*/
static VALUE
lazy_grep(VALUE obj, VALUE pattern)
{
const lazyenum_funcs *const funcs = rb_block_given_p() ?
&lazy_grep_iter_funcs : &lazy_grep_funcs;
return lazy_add_method(obj, 0, 0, pattern, rb_ary_new3(1, pattern), funcs);
}
static struct MEMO *
lazy_grep_v_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_index)
{
struct proc_entry *entry = proc_entry_ptr(proc_entry);
VALUE chain = rb_funcall(entry->memo, id_eqq, 1, result->memo_value);
if (RTEST(chain)) return 0;
return result;
}
static struct MEMO *
lazy_grep_v_iter_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_index)
{
struct proc_entry *entry = proc_entry_ptr(proc_entry);
VALUE value, chain = rb_funcall(entry->memo, id_eqq, 1, result->memo_value);
if (RTEST(chain)) return 0;
value = rb_proc_call_with_block(entry->proc, 1, &(result->memo_value), Qnil);
LAZY_MEMO_SET_VALUE(result, value);
LAZY_MEMO_RESET_PACKED(result);
return result;
}
static const lazyenum_funcs lazy_grep_v_iter_funcs = {
lazy_grep_v_iter_proc, 0,
};
static const lazyenum_funcs lazy_grep_v_funcs = {
lazy_grep_v_proc, 0,
};
/*
* call-seq:
* lazy.grep_v(pattern) -> lazy_enumerator
* lazy.grep_v(pattern) { |obj| block } -> lazy_enumerator
*
* Like Enumerable#grep_v, but chains operation to be lazy-evaluated.
*/
static VALUE
lazy_grep_v(VALUE obj, VALUE pattern)
{
const lazyenum_funcs *const funcs = rb_block_given_p() ?
&lazy_grep_v_iter_funcs : &lazy_grep_v_funcs;
return lazy_add_method(obj, 0, 0, pattern, rb_ary_new3(1, pattern), funcs);
}
static VALUE
call_next(VALUE obj)
{
return rb_funcall(obj, id_next, 0);
}
static VALUE
next_stopped(VALUE obj, VALUE _)
{
return Qnil;
}
static VALUE
lazy_zip_arrays_func(RB_BLOCK_CALL_FUNC_ARGLIST(val, arrays))
{
VALUE yielder, ary, memo;
long i, count;
yielder = argv[0];
memo = rb_attr_get(yielder, id_memo);
count = NIL_P(memo) ? 0 : NUM2LONG(memo);
ary = rb_ary_new2(RARRAY_LEN(arrays) + 1);
rb_ary_push(ary, argv[1]);
for (i = 0; i < RARRAY_LEN(arrays); i++) {
rb_ary_push(ary, rb_ary_entry(RARRAY_AREF(arrays, i), count));
}
rb_funcall(yielder, idLTLT, 1, ary);
rb_ivar_set(yielder, id_memo, LONG2NUM(++count));
return Qnil;
}
static VALUE
lazy_zip_func(RB_BLOCK_CALL_FUNC_ARGLIST(val, zip_args))
{
VALUE yielder, ary, arg, v;
long i;
yielder = argv[0];
arg = rb_attr_get(yielder, id_memo);
if (NIL_P(arg)) {
arg = rb_ary_new2(RARRAY_LEN(zip_args));
for (i = 0; i < RARRAY_LEN(zip_args); i++) {
rb_ary_push(arg, rb_funcall(RARRAY_AREF(zip_args, i), id_to_enum, 0));
}
rb_ivar_set(yielder, id_memo, arg);
}
ary = rb_ary_new2(RARRAY_LEN(arg) + 1);
v = Qnil;
if (--argc > 0) {
++argv;
v = argc > 1 ? rb_ary_new_from_values(argc, argv) : *argv;
}
rb_ary_push(ary, v);
for (i = 0; i < RARRAY_LEN(arg); i++) {
v = rb_rescue2(call_next, RARRAY_AREF(arg, i), next_stopped, 0,
rb_eStopIteration, (VALUE)0);
rb_ary_push(ary, v);
}
rb_funcall(yielder, idLTLT, 1, ary);
return Qnil;
}
/*
* call-seq:
* lazy.zip(arg, ...) -> lazy_enumerator
* lazy.zip(arg, ...) { |arr| block } -> nil
*
* Like Enumerable#zip, but chains operation to be lazy-evaluated.
* However, if a block is given to zip, values are enumerated immediately.
*/
static VALUE
lazy_zip(int argc, VALUE *argv, VALUE obj)
{
VALUE ary, v;
long i;
rb_block_call_func *func = lazy_zip_arrays_func;
if (rb_block_given_p()) {
return rb_call_super(argc, argv);
}
ary = rb_ary_new2(argc);
for (i = 0; i < argc; i++) {
v = rb_check_array_type(argv[i]);
if (NIL_P(v)) {
for (; i < argc; i++) {
if (!rb_respond_to(argv[i], id_each)) {
rb_raise(rb_eTypeError, "wrong argument type %"PRIsVALUE" (must respond to :each)",
rb_obj_class(argv[i]));
}
}
ary = rb_ary_new4(argc, argv);
func = lazy_zip_func;
break;
}
rb_ary_push(ary, v);
}
return lazy_set_method(rb_block_call(rb_cLazy, id_new, 1, &obj,
func, ary),
ary, lazy_receiver_size);
}
static struct MEMO *
lazy_take_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_index)
{
long remain;
struct proc_entry *entry = proc_entry_ptr(proc_entry);
VALUE memo = rb_ary_entry(memos, memo_index);
if (NIL_P(memo)) {
memo = entry->memo;
}
remain = NUM2LONG(memo);
if (remain == 0) {
LAZY_MEMO_SET_BREAK(result);
}
else {
if (--remain == 0) LAZY_MEMO_SET_BREAK(result);
rb_ary_store(memos, memo_index, LONG2NUM(remain));
}
return result;
}
static VALUE
lazy_take_size(VALUE entry, VALUE receiver)
{
long len = NUM2LONG(RARRAY_AREF(rb_ivar_get(entry, id_arguments), 0));
if (NIL_P(receiver) || (FIXNUM_P(receiver) && FIX2LONG(receiver) < len))
return receiver;
return LONG2NUM(len);
}
static const lazyenum_funcs lazy_take_funcs = {
lazy_take_proc, lazy_take_size,
};
/*
* call-seq:
* lazy.take(n) -> lazy_enumerator
*
* Like Enumerable#take, but chains operation to be lazy-evaluated.
*/
static VALUE
lazy_take(VALUE obj, VALUE n)
{
long len = NUM2LONG(n);
int argc = 0;
VALUE argv[2];
if (len < 0) {
rb_raise(rb_eArgError, "attempt to take negative size");
}
if (len == 0) {
argv[0] = sym_cycle;
argv[1] = INT2NUM(0);
argc = 2;
}
return lazy_add_method(obj, argc, argv, n, rb_ary_new3(1, n), &lazy_take_funcs);
}
static struct MEMO *
lazy_take_while_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_index)
{
VALUE take = lazyenum_yield_values(proc_entry, result);
if (!RTEST(take)) {
LAZY_MEMO_SET_BREAK(result);
return 0;
}
return result;
}
static const lazyenum_funcs lazy_take_while_funcs = {
lazy_take_while_proc, 0,
};
/*
* call-seq:
* lazy.take_while { |obj| block } -> lazy_enumerator
*
* Like Enumerable#take_while, but chains operation to be lazy-evaluated.
*/
static VALUE
lazy_take_while(VALUE obj)
{
if (!rb_block_given_p()) {
rb_raise(rb_eArgError, "tried to call lazy take_while without a block");
}
return lazy_add_method(obj, 0, 0, Qnil, Qnil, &lazy_take_while_funcs);
}
static VALUE
lazy_drop_size(VALUE proc_entry, VALUE receiver)
{
long len = NUM2LONG(RARRAY_AREF(rb_ivar_get(proc_entry, id_arguments), 0));
if (NIL_P(receiver))
return receiver;
if (FIXNUM_P(receiver)) {
len = FIX2LONG(receiver) - len;
return LONG2FIX(len < 0 ? 0 : len);
}
return rb_funcall(receiver, '-', 1, LONG2NUM(len));
}
static struct MEMO *
lazy_drop_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_index)
{
long remain;
struct proc_entry *entry = proc_entry_ptr(proc_entry);
VALUE memo = rb_ary_entry(memos, memo_index);
if (NIL_P(memo)) {
memo = entry->memo;
}
remain = NUM2LONG(memo);
if (remain > 0) {
--remain;
rb_ary_store(memos, memo_index, LONG2NUM(remain));
return 0;
}
return result;
}
static const lazyenum_funcs lazy_drop_funcs = {
lazy_drop_proc, lazy_drop_size,
};
/*
* call-seq:
* lazy.drop(n) -> lazy_enumerator
*
* Like Enumerable#drop, but chains operation to be lazy-evaluated.
*/
static VALUE
lazy_drop(VALUE obj, VALUE n)
{
long len = NUM2LONG(n);
VALUE argv[2];
argv[0] = sym_each;
argv[1] = n;
if (len < 0) {
rb_raise(rb_eArgError, "attempt to drop negative size");
}
return lazy_add_method(obj, 2, argv, n, rb_ary_new3(1, n), &lazy_drop_funcs);
}
static struct MEMO *
lazy_drop_while_proc(VALUE proc_entry, struct MEMO* result, VALUE memos, long memo_index)
{
struct proc_entry *entry = proc_entry_ptr(proc_entry);
VALUE memo = rb_ary_entry(memos, memo_index);
if (NIL_P(memo)) {
memo = entry->memo;
}
if (!RTEST(memo)) {
VALUE drop = lazyenum_yield_values(proc_entry, result);
if (RTEST(drop)) return 0;
rb_ary_store(memos, memo_index, Qtrue);
}
return result;
}
static const lazyenum_funcs lazy_drop_while_funcs = {
lazy_drop_while_proc, 0,
};
/*
* call-seq:
* lazy.drop_while { |obj| block } -> lazy_enumerator
*
* Like Enumerable#drop_while, but chains operation to be lazy-evaluated.
*/
static VALUE
lazy_drop_while(VALUE obj)
{
if (!rb_block_given_p()) {
rb_raise(rb_eArgError, "tried to call lazy drop_while without a block");
}
return lazy_add_method(obj, 0, 0, Qfalse, Qnil, &lazy_drop_while_funcs);
}
static int
lazy_uniq_check(VALUE chain, VALUE memos, long memo_index)
{
VALUE hash = rb_ary_entry(memos, memo_index);
if (NIL_P(hash)) {
hash = rb_obj_hide(rb_hash_new());
rb_ary_store(memos, memo_index, hash);
}
return rb_hash_add_new_element(hash, chain, Qfalse);
}
static struct MEMO *
lazy_uniq_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_index)
{
if (lazy_uniq_check(result->memo_value, memos, memo_index)) return 0;
return result;
}
static struct MEMO *
lazy_uniq_iter_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_index)
{
VALUE chain = lazyenum_yield(proc_entry, result);
if (lazy_uniq_check(chain, memos, memo_index)) return 0;
return result;
}
static const lazyenum_funcs lazy_uniq_iter_funcs = {
lazy_uniq_iter_proc, 0,
};
static const lazyenum_funcs lazy_uniq_funcs = {
lazy_uniq_proc, 0,
};
/*
* call-seq:
* lazy.uniq -> lazy_enumerator
* lazy.uniq { |item| ... } -> lazy_enumerator
*
* Like Enumerable#uniq, but chains operation to be lazy-evaluated.
*/
static VALUE
lazy_uniq(VALUE obj)
{
const lazyenum_funcs *const funcs =
rb_block_given_p() ? &lazy_uniq_iter_funcs : &lazy_uniq_funcs;
return lazy_add_method(obj, 0, 0, Qnil, Qnil, funcs);
}
#if 0 /* for RDoc */
/*
* call-seq:
* lazy.chunk { |elt| ... } -> lazy_enumerator
*
* Like Enumerable#chunk, but chains operation to be lazy-evaluated.
*/
static VALUE lazy_chunk(VALUE self)
{
}
/*
* call-seq:
* lazy.chunk_while {|elt_before, elt_after| bool } -> lazy_enumerator
*
* Like Enumerable#chunk_while, but chains operation to be lazy-evaluated.
*/
static VALUE lazy_chunk_while(VALUE self)
{
}
/*
* call-seq:
* lazy.slice_after(pattern) -> lazy_enumerator
* lazy.slice_after { |elt| bool } -> lazy_enumerator
*
* Like Enumerable#slice_after, but chains operation to be lazy-evaluated.
*/
static VALUE lazy_slice_after(VALUE self)
{
}
/*
* call-seq:
* lazy.slice_before(pattern) -> lazy_enumerator
* lazy.slice_before { |elt| bool } -> lazy_enumerator
*
* Like Enumerable#slice_before, but chains operation to be lazy-evaluated.
*/
static VALUE lazy_slice_before(VALUE self)
{
}
/*
* call-seq:
* lazy.slice_when {|elt_before, elt_after| bool } -> lazy_enumerator
*
* Like Enumerable#slice_when, but chains operation to be lazy-evaluated.
*/
static VALUE lazy_slice_when(VALUE self)
{
}
# endif
static VALUE
lazy_super(int argc, VALUE *argv, VALUE lazy)
{
return enumerable_lazy(rb_call_super(argc, argv));
}
/*
* call-seq:
* enum.lazy -> lazy_enumerator
*
* Returns self.
*/
static VALUE
lazy_lazy(VALUE obj)
{
return obj;
}
/*
* Document-class: StopIteration
*
* Raised to stop the iteration, in particular by Enumerator#next. It is
* rescued by Kernel#loop.
*
* loop do
* puts "Hello"
* raise StopIteration
* puts "World"
* end
* puts "Done!"
*
* <em>produces:</em>
*
* Hello
* Done!
*/
/*
* call-seq:
* result -> value
*
* Returns the return value of the iterator.
*
* o = Object.new
* def o.each
* yield 1
* yield 2
* yield 3
* 100
* end
*
* e = o.to_enum
*
* puts e.next #=> 1
* puts e.next #=> 2
* puts e.next #=> 3
*
* begin
* e.next
* rescue StopIteration => ex
* puts ex.result #=> 100
* end
*
*/
static VALUE
stop_result(VALUE self)
{
return rb_attr_get(self, id_result);
}
/*
* Producer
*/
static void
producer_mark(void *p)
{
struct producer *ptr = p;
rb_gc_mark_movable(ptr->init);
rb_gc_mark_movable(ptr->proc);
}
static void
producer_compact(void *p)
{
struct producer *ptr = p;
ptr->init = rb_gc_location(ptr->init);
ptr->proc = rb_gc_location(ptr->proc);
}
#define producer_free RUBY_TYPED_DEFAULT_FREE
static size_t
producer_memsize(const void *p)
{
return sizeof(struct producer);
}
static const rb_data_type_t producer_data_type = {
"producer",
{
producer_mark,
producer_free,
producer_memsize,
producer_compact,
},
0, 0, RUBY_TYPED_FREE_IMMEDIATELY
};
static struct producer *
producer_ptr(VALUE obj)
{
struct producer *ptr;
TypedData_Get_Struct(obj, struct producer, &producer_data_type, ptr);
if (!ptr || ptr->proc == Qundef) {
rb_raise(rb_eArgError, "uninitialized producer");
}
return ptr;
}
/* :nodoc: */
static VALUE
producer_allocate(VALUE klass)
{
struct producer *ptr;
VALUE obj;
obj = TypedData_Make_Struct(klass, struct producer, &producer_data_type, ptr);
ptr->init = Qundef;
ptr->proc = Qundef;
return obj;
}
static VALUE
producer_init(VALUE obj, VALUE init, VALUE proc)
{
struct producer *ptr;
TypedData_Get_Struct(obj, struct producer, &producer_data_type, ptr);
if (!ptr) {
rb_raise(rb_eArgError, "unallocated producer");
}
ptr->init = init;
ptr->proc = proc;
return obj;
}
static VALUE
producer_each_stop(VALUE dummy, VALUE exc)
{
return rb_attr_get(exc, id_result);
}
static VALUE
producer_each_i(VALUE obj)
{
struct producer *ptr;
VALUE init, proc, curr;
ptr = producer_ptr(obj);
init = ptr->init;
proc = ptr->proc;
if (init == Qundef) {
curr = Qnil;
} else {
rb_yield(init);
curr = init;
}
for (;;) {
curr = rb_funcall(proc, id_call, 1, curr);
rb_yield(curr);
}
return Qnil;
}
/* :nodoc: */
static VALUE
producer_each(VALUE obj)
{
rb_need_block();
return rb_rescue2(producer_each_i, obj, producer_each_stop, (VALUE)0, rb_eStopIteration, (VALUE)0);
}
static VALUE
producer_size(VALUE obj, VALUE args, VALUE eobj)
{
return DBL2NUM(HUGE_VAL);
}
/*
* call-seq:
* Enumerator.produce(initial = nil) { |val| } -> enumerator
*
* Creates an infinite enumerator from any block, just called over and
* over. Result of the previous iteration is passed to the next one.
* If +initial+ is provided, it is passed to the first iteration, and
* becomes the first element of the enumerator; if it is not provided,
* first iteration receives +nil+, and its result becomes first
* element of the iterator.
*
* Raising StopIteration from the block stops an iteration.
*
* Examples of usage:
*
* Enumerator.produce(1, &:succ) # => enumerator of 1, 2, 3, 4, ....
*
* Enumerator.produce { rand(10) } # => infinite random number sequence
*
* ancestors = Enumerator.produce(node) { |prev| node = prev.parent or raise StopIteration }
* enclosing_section = ancestors.find { |n| n.type == :section }
*
* Using ::produce together with Enumerable methods like Enumerable#detect,
* Enumerable#slice, Enumerable#take_while can provide Enumerator-based alternative
* for +while+ and +until+ cycles:
*
* # Find next Tuesday
* require 'date'
* Enumerator.produce(Date.today, &:succ).detect(&:tuesday?)
*
* # Simple lexer:
* require 'strscan'
* scanner = StringScanner.new('7+38/6')
* PATTERN = %r{\d+|[-/+*]}
* p Enumerator.produce { scanner.scan(PATTERN) }.slice_after { scanner.eos? }.first
* # => ["7", "+", "38", "/", "6"]
*/
static VALUE
enumerator_s_produce(int argc, VALUE *argv, VALUE klass)
{
VALUE init, producer;
if (!rb_block_given_p()) rb_raise(rb_eArgError, "no block given");
if (rb_scan_args(argc, argv, "01", &init) == 0) {
init = Qundef;
}
producer = producer_init(producer_allocate(rb_cEnumProducer), init, rb_block_proc());
return rb_enumeratorize_with_size_kw(producer, sym_each, 0, 0, producer_size, RB_NO_KEYWORDS);
}
/*
* Document-class: Enumerator::Chain
*
* Enumerator::Chain is a subclass of Enumerator, which represents a
* chain of enumerables that works as a single enumerator.
*
* This type of objects can be created by Enumerable#chain and
* Enumerator#+.
*/
static void
enum_chain_mark(void *p)
{
struct enum_chain *ptr = p;
rb_gc_mark_movable(ptr->enums);
}
static void
enum_chain_compact(void *p)
{
struct enum_chain *ptr = p;
ptr->enums = rb_gc_location(ptr->enums);
}
#define enum_chain_free RUBY_TYPED_DEFAULT_FREE
static size_t
enum_chain_memsize(const void *p)
{
return sizeof(struct enum_chain);
}
static const rb_data_type_t enum_chain_data_type = {
"chain",
{
enum_chain_mark,
enum_chain_free,
enum_chain_memsize,
enum_chain_compact,
},
0, 0, RUBY_TYPED_FREE_IMMEDIATELY
};
static struct enum_chain *
enum_chain_ptr(VALUE obj)
{
struct enum_chain *ptr;
TypedData_Get_Struct(obj, struct enum_chain, &enum_chain_data_type, ptr);
if (!ptr || ptr->enums == Qundef) {
rb_raise(rb_eArgError, "uninitialized chain");
}
return ptr;
}
/* :nodoc: */
static VALUE
enum_chain_allocate(VALUE klass)
{
struct enum_chain *ptr;
VALUE obj;
obj = TypedData_Make_Struct(klass, struct enum_chain, &enum_chain_data_type, ptr);
ptr->enums = Qundef;
ptr->pos = -1;
return obj;
}
/*
* call-seq:
* Enumerator::Chain.new(*enums) -> enum
*
* Generates a new enumerator object that iterates over the elements
* of given enumerable objects in sequence.
*
* e = Enumerator::Chain.new(1..3, [4, 5])
* e.to_a #=> [1, 2, 3, 4, 5]
* e.size #=> 5
*/
static VALUE
enum_chain_initialize(VALUE obj, VALUE enums)
{
struct enum_chain *ptr;
rb_check_frozen(obj);
TypedData_Get_Struct(obj, struct enum_chain, &enum_chain_data_type, ptr);
if (!ptr) rb_raise(rb_eArgError, "unallocated chain");
ptr->enums = rb_obj_freeze(enums);
ptr->pos = -1;
return obj;
}
/* :nodoc: */
static VALUE
enum_chain_init_copy(VALUE obj, VALUE orig)
{
struct enum_chain *ptr0, *ptr1;
if (!OBJ_INIT_COPY(obj, orig)) return obj;
ptr0 = enum_chain_ptr(orig);
TypedData_Get_Struct(obj, struct enum_chain, &enum_chain_data_type, ptr1);
if (!ptr1) rb_raise(rb_eArgError, "unallocated chain");
ptr1->enums = ptr0->enums;
ptr1->pos = ptr0->pos;
return obj;
}
static VALUE
enum_chain_total_size(VALUE enums)
{
VALUE total = INT2FIX(0);
long i;
for (i = 0; i < RARRAY_LEN(enums); i++) {
VALUE size = enum_size(RARRAY_AREF(enums, i));
if (NIL_P(size) || (RB_TYPE_P(size, T_FLOAT) && isinf(NUM2DBL(size)))) {
return size;
}
if (!RB_INTEGER_TYPE_P(size)) {
return Qnil;
}
total = rb_funcall(total, '+', 1, size);
}
return total;
}
/*
* call-seq:
* obj.size -> int, Float::INFINITY or nil
*
* Returns the total size of the enumerator chain calculated by
* summing up the size of each enumerable in the chain. If any of the
* enumerables reports its size as nil or Float::INFINITY, that value
* is returned as the total size.
*/
static VALUE
enum_chain_size(VALUE obj)
{
return enum_chain_total_size(enum_chain_ptr(obj)->enums);
}
static VALUE
enum_chain_enum_size(VALUE obj, VALUE args, VALUE eobj)
{
return enum_chain_size(obj);
}
static VALUE
enum_chain_yield_block(RB_BLOCK_CALL_FUNC_ARGLIST(_, block))
{
return rb_funcallv(block, id_call, argc, argv);
}
static VALUE
enum_chain_enum_no_size(VALUE obj, VALUE args, VALUE eobj)
{
return Qnil;
}
/*
* call-seq:
* obj.each(*args) { |...| ... } -> obj
* obj.each(*args) -> enumerator
*
* Iterates over the elements of the first enumerable by calling the
* "each" method on it with the given arguments, then proceeds to the
* following enumerables in sequence until all of the enumerables are
* exhausted.
*
* If no block is given, returns an enumerator.
*/
static VALUE
enum_chain_each(int argc, VALUE *argv, VALUE obj)
{
VALUE enums, block;
struct enum_chain *objptr;
long i;
RETURN_SIZED_ENUMERATOR(obj, argc, argv, argc > 0 ? enum_chain_enum_no_size : enum_chain_enum_size);
objptr = enum_chain_ptr(obj);
enums = objptr->enums;
block = rb_block_proc();
for (i = 0; i < RARRAY_LEN(enums); i++) {
objptr->pos = i;
rb_block_call(RARRAY_AREF(enums, i), id_each, argc, argv, enum_chain_yield_block, block);
}
return obj;
}
/*
* call-seq:
* obj.rewind -> obj
*
* Rewinds the enumerator chain by calling the "rewind" method on each
* enumerable in reverse order. Each call is performed only if the
* enumerable responds to the method.
*/
static VALUE
enum_chain_rewind(VALUE obj)
{
struct enum_chain *objptr = enum_chain_ptr(obj);
VALUE enums = objptr->enums;
long i;
for (i = objptr->pos; 0 <= i && i < RARRAY_LEN(enums); objptr->pos = --i) {
rb_check_funcall(RARRAY_AREF(enums, i), id_rewind, 0, 0);
}
return obj;
}
static VALUE
inspect_enum_chain(VALUE obj, VALUE dummy, int recur)
{
VALUE klass = rb_obj_class(obj);
struct enum_chain *ptr;
TypedData_Get_Struct(obj, struct enum_chain, &enum_chain_data_type, ptr);
if (!ptr || ptr->enums == Qundef) {
return rb_sprintf("#<%"PRIsVALUE": uninitialized>", rb_class_path(klass));
}
if (recur) {
return rb_sprintf("#<%"PRIsVALUE": ...>", rb_class_path(klass));
}
return rb_sprintf("#<%"PRIsVALUE": %+"PRIsVALUE">", rb_class_path(klass), ptr->enums);
}
/*
* call-seq:
* obj.inspect -> string
*
* Returns a printable version of the enumerator chain.
*/
static VALUE
enum_chain_inspect(VALUE obj)
{
return rb_exec_recursive(inspect_enum_chain, obj, 0);
}
/*
* call-seq:
* e.chain(*enums) -> enumerator
*
* Returns an enumerator object generated from this enumerator and
* given enumerables.
*
* e = (1..3).chain([4, 5])
* e.to_a #=> [1, 2, 3, 4, 5]
*/
static VALUE
enum_chain(int argc, VALUE *argv, VALUE obj)
{
VALUE enums = rb_ary_new_from_values(1, &obj);
rb_ary_cat(enums, argv, argc);
return enum_chain_initialize(enum_chain_allocate(rb_cEnumChain), enums);
}
/*
* call-seq:
* e + enum -> enumerator
*
* Returns an enumerator object generated from this enumerator and a
* given enumerable.
*
* e = (1..3).each + [4, 5]
* e.to_a #=> [1, 2, 3, 4, 5]
*/
static VALUE
enumerator_plus(VALUE obj, VALUE eobj)
{
VALUE enums = rb_ary_new_from_args(2, obj, eobj);
return enum_chain_initialize(enum_chain_allocate(rb_cEnumChain), enums);
}
/*
* Document-class: Enumerator::ArithmeticSequence
*
* Enumerator::ArithmeticSequence is a subclass of Enumerator,
* that is a representation of sequences of numbers with common difference.
* Instances of this class can be generated by the Range#step and Numeric#step
* methods.
*/
VALUE
rb_arith_seq_new(VALUE obj, VALUE meth, int argc, VALUE const *argv,
rb_enumerator_size_func *size_fn,
VALUE beg, VALUE end, VALUE step, int excl)
{
VALUE aseq = enumerator_init(enumerator_allocate(rb_cArithSeq),
obj, meth, argc, argv, size_fn, Qnil, PASS_KW_SPLAT);
rb_ivar_set(aseq, id_begin, beg);
rb_ivar_set(aseq, id_end, end);
rb_ivar_set(aseq, id_step, step);
rb_ivar_set(aseq, id_exclude_end, excl ? Qtrue : Qfalse);
return aseq;
}
/*
* call-seq: aseq.begin -> num or nil
*
* Returns the number that defines the first element of this arithmetic
* sequence.
*/
static inline VALUE
arith_seq_begin(VALUE self)
{
return rb_ivar_get(self, id_begin);
}
/*
* call-seq: aseq.end -> num or nil
*
* Returns the number that defines the end of this arithmetic sequence.
*/
static inline VALUE
arith_seq_end(VALUE self)
{
return rb_ivar_get(self, id_end);
}
/*
* call-seq: aseq.step -> num
*
* Returns the number that defines the common difference between
* two adjacent elements in this arithmetic sequence.
*/
static inline VALUE
arith_seq_step(VALUE self)
{
return rb_ivar_get(self, id_step);
}
/*
* call-seq: aseq.exclude_end? -> true or false
*
* Returns <code>true</code> if this arithmetic sequence excludes its end value.
*/
static inline VALUE
arith_seq_exclude_end(VALUE self)
{
return rb_ivar_get(self, id_exclude_end);
}
static inline int
arith_seq_exclude_end_p(VALUE self)
{
return RTEST(arith_seq_exclude_end(self));
}
int
rb_arithmetic_sequence_extract(VALUE obj, rb_arithmetic_sequence_components_t *component)
{
if (rb_obj_is_kind_of(obj, rb_cArithSeq)) {
component->begin = arith_seq_begin(obj);
component->end = arith_seq_end(obj);
component->step = arith_seq_step(obj);
component->exclude_end = arith_seq_exclude_end_p(obj);
return 1;
}
else if (rb_obj_is_kind_of(obj, rb_cRange)) {
component->begin = RANGE_BEG(obj);
component->end = RANGE_END(obj);
component->step = INT2FIX(1);
component->exclude_end = RTEST(RANGE_EXCL(obj));
return 1;
}
return 0;
}
/*
* call-seq:
* aseq.first -> num or nil
* aseq.first(n) -> an_array
*
* Returns the first number in this arithmetic sequence,
* or an array of the first +n+ elements.
*/
static VALUE
arith_seq_first(int argc, VALUE *argv, VALUE self)
{
VALUE b, e, s, ary;
long n;
int x;
rb_check_arity(argc, 0, 1);
b = arith_seq_begin(self);
e = arith_seq_end(self);
s = arith_seq_step(self);
if (argc == 0) {
if (NIL_P(b)) {
return Qnil;
}
if (!NIL_P(e)) {
VALUE zero = INT2FIX(0);
int r = rb_cmpint(rb_num_coerce_cmp(s, zero, idCmp), s, zero);
if (r > 0 && RTEST(rb_funcall(b, '>', 1, e))) {
return Qnil;
}
if (r < 0 && RTEST(rb_funcall(b, '<', 1, e))) {
return Qnil;
}
}
return b;
}
// TODO: the following code should be extracted as arith_seq_take
n = NUM2LONG(argv[0]);
if (n < 0) {
rb_raise(rb_eArgError, "attempt to take negative size");
}
if (n == 0) {
return rb_ary_new_capa(0);
}
x = arith_seq_exclude_end_p(self);
if (FIXNUM_P(b) && NIL_P(e) && FIXNUM_P(s)) {
long i = FIX2LONG(b), unit = FIX2LONG(s);
ary = rb_ary_new_capa(n);
while (n > 0 && FIXABLE(i)) {
rb_ary_push(ary, LONG2FIX(i));
i += unit; // FIXABLE + FIXABLE never overflow;
--n;
}
if (n > 0) {
b = LONG2NUM(i);
while (n > 0) {
rb_ary_push(ary, b);
b = rb_big_plus(b, s);
--n;
}
}
return ary;
}
else if (FIXNUM_P(b) && FIXNUM_P(e) && FIXNUM_P(s)) {
long i = FIX2LONG(b);
long end = FIX2LONG(e);
long unit = FIX2LONG(s);
long len;
if (unit >= 0) {
if (!x) end += 1;
len = end - i;
if (len < 0) len = 0;
ary = rb_ary_new_capa((n < len) ? n : len);
while (n > 0 && i < end) {
rb_ary_push(ary, LONG2FIX(i));
if (i + unit < i) break;
i += unit;
--n;
}
}
else {
if (!x) end -= 1;
len = i - end;
if (len < 0) len = 0;
ary = rb_ary_new_capa((n < len) ? n : len);
while (n > 0 && i > end) {
rb_ary_push(ary, LONG2FIX(i));
if (i + unit > i) break;
i += unit;
--n;
}
}
return ary;
}
else if (RB_FLOAT_TYPE_P(b) || RB_FLOAT_TYPE_P(e) || RB_FLOAT_TYPE_P(s)) {
/* generate values like ruby_float_step */
double unit = NUM2DBL(s);
double beg = NUM2DBL(b);
double end = NIL_P(e) ? (unit < 0 ? -1 : 1)*HUGE_VAL : NUM2DBL(e);
double len = ruby_float_step_size(beg, end, unit, x);
long i;
if (n > len)
n = (long)len;
if (isinf(unit)) {
if (len > 0) {
ary = rb_ary_new_capa(1);
rb_ary_push(ary, DBL2NUM(beg));
}
else {
ary = rb_ary_new_capa(0);
}
}
else if (unit == 0) {
VALUE val = DBL2NUM(beg);
ary = rb_ary_new_capa(n);
for (i = 0; i < len; ++i) {
rb_ary_push(ary, val);
}
}
else {
ary = rb_ary_new_capa(n);
for (i = 0; i < n; ++i) {
double d = i*unit+beg;
if (unit >= 0 ? end < d : d < end) d = end;
rb_ary_push(ary, DBL2NUM(d));
}
}
return ary;
}
return rb_call_super(argc, argv);
}
/*
* call-seq:
* aseq.last -> num or nil
* aseq.last(n) -> an_array
*
* Returns the last number in this arithmetic sequence,
* or an array of the last +n+ elements.
*/
static VALUE
arith_seq_last(int argc, VALUE *argv, VALUE self)
{
VALUE b, e, s, len_1, len, last, nv, ary;
int last_is_adjusted;
long n;
e = arith_seq_end(self);
if (NIL_P(e)) {
rb_raise(rb_eRangeError,
"cannot get the last element of endless arithmetic sequence");
}
b = arith_seq_begin(self);
s = arith_seq_step(self);
len_1 = rb_int_idiv(rb_int_minus(e, b), s);
if (rb_num_negative_int_p(len_1)) {
if (argc == 0) {
return Qnil;
}
return rb_ary_new_capa(0);
}
last = rb_int_plus(b, rb_int_mul(s, len_1));
if ((last_is_adjusted = arith_seq_exclude_end_p(self) && rb_equal(last, e))) {
last = rb_int_minus(last, s);
}
if (argc == 0) {
return last;
}
if (last_is_adjusted) {
len = len_1;
}
else {
len = rb_int_plus(len_1, INT2FIX(1));
}
rb_scan_args(argc, argv, "1", &nv);
if (!RB_INTEGER_TYPE_P(nv)) {
nv = rb_to_int(nv);
}
if (RTEST(rb_int_gt(nv, len))) {
nv = len;
}
n = NUM2LONG(nv);
if (n < 0) {
rb_raise(rb_eArgError, "negative array size");
}
ary = rb_ary_new_capa(n);
b = rb_int_minus(last, rb_int_mul(s, nv));
while (n) {
b = rb_int_plus(b, s);
rb_ary_push(ary, b);
--n;
}
return ary;
}
/*
* call-seq:
* aseq.inspect -> string
*
* Convert this arithmetic sequence to a printable form.
*/
static VALUE
arith_seq_inspect(VALUE self)
{
struct enumerator *e;
VALUE eobj, str, eargs;
int range_p;
TypedData_Get_Struct(self, struct enumerator, &enumerator_data_type, e);
eobj = rb_attr_get(self, id_receiver);
if (NIL_P(eobj)) {
eobj = e->obj;
}
range_p = RTEST(rb_obj_is_kind_of(eobj, rb_cRange));
str = rb_sprintf("(%s%"PRIsVALUE"%s.", range_p ? "(" : "", eobj, range_p ? ")" : "");
rb_str_buf_append(str, rb_id2str(e->meth));
eargs = rb_attr_get(eobj, id_arguments);
if (NIL_P(eargs)) {
eargs = e->args;
}
if (eargs != Qfalse) {
long argc = RARRAY_LEN(eargs);
const VALUE *argv = RARRAY_CONST_PTR(eargs); /* WB: no new reference */
if (argc > 0) {
VALUE kwds = Qnil;
rb_str_buf_cat2(str, "(");
if (RB_TYPE_P(argv[argc-1], T_HASH)) {
int all_key = TRUE;
rb_hash_foreach(argv[argc-1], key_symbol_p, (VALUE)&all_key);
if (all_key) kwds = argv[--argc];
}
while (argc--) {
VALUE arg = *argv++;
rb_str_append(str, rb_inspect(arg));
rb_str_buf_cat2(str, ", ");
}
if (!NIL_P(kwds)) {
rb_hash_foreach(kwds, kwd_append, str);
}
rb_str_set_len(str, RSTRING_LEN(str)-2); /* drop the last ", " */
rb_str_buf_cat2(str, ")");
}
}
rb_str_buf_cat2(str, ")");
return str;
}
/*
* call-seq:
* aseq == obj -> true or false
*
* Returns <code>true</code> only if +obj+ is an Enumerator::ArithmeticSequence,
* has equivalent begin, end, step, and exclude_end? settings.
*/
static VALUE
arith_seq_eq(VALUE self, VALUE other)
{
if (!RTEST(rb_obj_is_kind_of(other, rb_cArithSeq))) {
return Qfalse;
}
if (!rb_equal(arith_seq_begin(self), arith_seq_begin(other))) {
return Qfalse;
}
if (!rb_equal(arith_seq_end(self), arith_seq_end(other))) {
return Qfalse;
}
if (!rb_equal(arith_seq_step(self), arith_seq_step(other))) {
return Qfalse;
}
if (arith_seq_exclude_end_p(self) != arith_seq_exclude_end_p(other)) {
return Qfalse;
}
return Qtrue;
}
/*
* call-seq:
* aseq.hash -> integer
*
* Compute a hash-value for this arithmetic sequence.
* Two arithmetic sequences with same begin, end, step, and exclude_end?
* values will generate the same hash-value.
*
* See also Object#hash.
*/
static VALUE
arith_seq_hash(VALUE self)
{
st_index_t hash;
VALUE v;
hash = rb_hash_start(arith_seq_exclude_end_p(self));
v = rb_hash(arith_seq_begin(self));
hash = rb_hash_uint(hash, NUM2LONG(v));
v = rb_hash(arith_seq_end(self));
hash = rb_hash_uint(hash, NUM2LONG(v));
v = rb_hash(arith_seq_step(self));
hash = rb_hash_uint(hash, NUM2LONG(v));
hash = rb_hash_end(hash);
return ST2FIX(hash);
}
#define NUM_GE(x, y) RTEST(rb_num_coerce_relop((x), (y), idGE))
struct arith_seq_gen {
VALUE current;
VALUE end;
VALUE step;
int excl;
};
/*
* call-seq:
* aseq.each {|i| block } -> aseq
* aseq.each -> aseq
*/
static VALUE
arith_seq_each(VALUE self)
{
VALUE c, e, s, len_1, last;
int x;
if (!rb_block_given_p()) return self;
c = arith_seq_begin(self);
e = arith_seq_end(self);
s = arith_seq_step(self);
x = arith_seq_exclude_end_p(self);
if (!RB_TYPE_P(s, T_COMPLEX) && ruby_float_step(c, e, s, x, TRUE)) {
return self;
}
if (NIL_P(e)) {
while (1) {
rb_yield(c);
c = rb_int_plus(c, s);
}
return self;
}
if (rb_equal(s, INT2FIX(0))) {
while (1) {
rb_yield(c);
}
return self;
}
len_1 = rb_int_idiv(rb_int_minus(e, c), s);
last = rb_int_plus(c, rb_int_mul(s, len_1));
if (x && rb_equal(last, e)) {
last = rb_int_minus(last, s);
}
if (rb_num_negative_int_p(s)) {
while (NUM_GE(c, last)) {
rb_yield(c);
c = rb_int_plus(c, s);
}
}
else {
while (NUM_GE(last, c)) {
rb_yield(c);
c = rb_int_plus(c, s);
}
}
return self;
}
static double
arith_seq_float_step_size(double beg, double end, double step, int excl)
{
double const epsilon = DBL_EPSILON;
double n, err;
if (step == 0) {
return HUGE_VAL;
}
n = (end - beg) / step;
err = (fabs(beg) + fabs(end) + fabs(end - beg)) / fabs(step) * epsilon;
if (isinf(step)) {
return step > 0 ? beg <= end : beg >= end;
}
if (err > 0.5) err = 0.5;
if (excl) {
if (n <= 0) return 0;
if (n < 1)
n = 0;
else
n = floor(n - err);
}
else {
if (n < 0) return 0;
n = floor(n + err);
}
return n + 1;
}
/*
* call-seq:
* aseq.size -> num or nil
*
* Returns the number of elements in this arithmetic sequence if it is a finite
* sequence. Otherwise, returns <code>nil</code>.
*/
static VALUE
arith_seq_size(VALUE self)
{
VALUE b, e, s, len_1, len, last;
int x;
b = arith_seq_begin(self);
e = arith_seq_end(self);
s = arith_seq_step(self);
x = arith_seq_exclude_end_p(self);
if (RB_FLOAT_TYPE_P(b) || RB_FLOAT_TYPE_P(e) || RB_FLOAT_TYPE_P(s)) {
double ee, n;
if (NIL_P(e)) {
if (rb_num_negative_int_p(s)) {
ee = -HUGE_VAL;
}
else {
ee = HUGE_VAL;
}
}
else {
ee = NUM2DBL(e);
}
n = arith_seq_float_step_size(NUM2DBL(b), ee, NUM2DBL(s), x);
if (isinf(n)) return DBL2NUM(n);
if (POSFIXABLE(n)) return LONG2FIX(n);
return rb_dbl2big(n);
}
if (NIL_P(e)) {
return DBL2NUM(HUGE_VAL);
}
if (!rb_obj_is_kind_of(s, rb_cNumeric)) {
s = rb_to_int(s);
}
if (rb_equal(s, INT2FIX(0))) {
return DBL2NUM(HUGE_VAL);
}
len_1 = rb_int_idiv(rb_int_minus(e, b), s);
if (rb_num_negative_int_p(len_1)) {
return INT2FIX(0);
}
last = rb_int_plus(b, rb_int_mul(s, len_1));
if (x && rb_equal(last, e)) {
len = len_1;
}
else {
len = rb_int_plus(len_1, INT2FIX(1));
}
return len;
}
static VALUE
lazy_with_index_func(RB_BLOCK_CALL_FUNC_ARGLIST(val, offset))
{
VALUE yielder, memo, result;
VALUE e = rb_enum_values_pack(argc - 1, argv + 1);
long idx;
yielder = argv[0];
memo = rb_attr_get(yielder, id_memo);
if (NIL_P(memo))
memo = offset;
idx = NUM2LONG(memo);
result = rb_assoc_new(e, memo);
rb_funcall(yielder, idLTLT, 1, result);
rb_ivar_set(yielder, id_memo, LONG2NUM(++idx));
return Qnil;
}
static VALUE
lazy_with_index_iter(RB_BLOCK_CALL_FUNC_ARGLIST(val, offset))
{
VALUE yielder, memo, result;
VALUE e = rb_enum_values_pack(argc - 1, argv + 1);
long idx;
yielder = argv[0];
memo = rb_attr_get(yielder, id_memo);
if (NIL_P(memo))
memo = offset;
idx = NUM2LONG(memo);
result = rb_yield(rb_assoc_new(e, memo));
rb_funcall(yielder, idLTLT, 1, result);
rb_ivar_set(yielder, id_memo, LONG2NUM(++idx));
return Qnil;
}
/*
* call-seq:
* lazy.with_index(offset = 0) {|(*args), idx| ... }
* lazy.with_index(offset = 0)
*
* Iterates the given block for each element with an index, which
* starts from +offset+. If no block is given, returns a new
* lazy enumerator that includes the index, starting from +offset+
*
* +offset+:: the starting index to use
*
* see Enumerator#with_index.
*/
static VALUE
lazy_with_index(int argc, VALUE *argv, VALUE obj)
{
VALUE memo;
rb_scan_args(argc, argv, "01", &memo);
if (NIL_P(memo))
memo = LONG2NUM(0);
return lazy_set_method(rb_block_call(rb_cLazy, id_new, 1, &obj,
rb_block_given_p() ?
lazy_with_index_iter : lazy_with_index_func,
memo),
rb_ary_new_from_values(argc, argv), 0);
}
void
InitVM_Enumerator(void)
{
ID id_private = rb_intern("private");
rb_define_method(rb_mKernel, "to_enum", obj_to_enum, -1);
rb_define_method(rb_mKernel, "enum_for", obj_to_enum, -1);
rb_cEnumerator = rb_define_class("Enumerator", rb_cObject);
rb_include_module(rb_cEnumerator, rb_mEnumerable);
rb_define_alloc_func(rb_cEnumerator, enumerator_allocate);
rb_define_method(rb_cEnumerator, "initialize", enumerator_initialize, -1);
rb_define_method(rb_cEnumerator, "initialize_copy", enumerator_init_copy, 1);
rb_define_method(rb_cEnumerator, "each", enumerator_each, -1);
rb_define_method(rb_cEnumerator, "each_with_index", enumerator_each_with_index, 0);
rb_define_method(rb_cEnumerator, "each_with_object", enumerator_with_object, 1);
rb_define_method(rb_cEnumerator, "with_index", enumerator_with_index, -1);
rb_define_method(rb_cEnumerator, "with_object", enumerator_with_object, 1);
rb_define_method(rb_cEnumerator, "next_values", enumerator_next_values, 0);
rb_define_method(rb_cEnumerator, "peek_values", enumerator_peek_values_m, 0);
rb_define_method(rb_cEnumerator, "next", enumerator_next, 0);
rb_define_method(rb_cEnumerator, "peek", enumerator_peek, 0);
rb_define_method(rb_cEnumerator, "feed", enumerator_feed, 1);
rb_define_method(rb_cEnumerator, "rewind", enumerator_rewind, 0);
rb_define_method(rb_cEnumerator, "inspect", enumerator_inspect, 0);
rb_define_method(rb_cEnumerator, "size", enumerator_size, 0);
rb_define_method(rb_cEnumerator, "+", enumerator_plus, 1);
rb_define_method(rb_mEnumerable, "chain", enum_chain, -1);
/* Lazy */
rb_cLazy = rb_define_class_under(rb_cEnumerator, "Lazy", rb_cEnumerator);
rb_define_method(rb_mEnumerable, "lazy", enumerable_lazy, 0);
rb_define_alias(rb_cLazy, "_enumerable_map", "map");
rb_define_alias(rb_cLazy, "_enumerable_collect", "collect");
rb_define_alias(rb_cLazy, "_enumerable_flat_map", "flat_map");
rb_define_alias(rb_cLazy, "_enumerable_collect_concat", "collect_concat");
rb_define_alias(rb_cLazy, "_enumerable_select", "select");
rb_define_alias(rb_cLazy, "_enumerable_find_all", "find_all");
rb_define_alias(rb_cLazy, "_enumerable_filter", "filter");
rb_define_alias(rb_cLazy, "_enumerable_filter_map", "filter_map");
rb_define_alias(rb_cLazy, "_enumerable_reject", "reject");
rb_define_alias(rb_cLazy, "_enumerable_grep", "grep");
rb_define_alias(rb_cLazy, "_enumerable_grep_v", "grep_v");
rb_define_alias(rb_cLazy, "_enumerable_zip", "zip");
rb_define_alias(rb_cLazy, "_enumerable_take", "take");
rb_define_alias(rb_cLazy, "_enumerable_take_while", "take_while");
rb_define_alias(rb_cLazy, "_enumerable_drop", "drop");
rb_define_alias(rb_cLazy, "_enumerable_drop_while", "drop_while");
rb_define_alias(rb_cLazy, "_enumerable_uniq", "uniq");
rb_define_private_method(rb_cLazy, "_enumerable_with_index", enumerator_with_index, -1);
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_map")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_collect")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_flat_map")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_collect_concat")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_select")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_find_all")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_filter")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_filter_map")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_reject")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_grep")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_grep_v")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_zip")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_take")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_take_while")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_drop")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_drop_while")));
rb_funcall(rb_cLazy, id_private, 1, ID2SYM(rb_intern("_enumerable_uniq")));
rb_define_method(rb_cLazy, "initialize", lazy_initialize, -1);
rb_define_method(rb_cLazy, "to_enum", lazy_to_enum, -1);
rb_define_method(rb_cLazy, "enum_for", lazy_to_enum, -1);
rb_define_method(rb_cLazy, "eager", lazy_eager, 0);
rb_define_method(rb_cLazy, "map", lazy_map, 0);
rb_define_method(rb_cLazy, "collect", lazy_map, 0);
rb_define_method(rb_cLazy, "flat_map", lazy_flat_map, 0);
rb_define_method(rb_cLazy, "collect_concat", lazy_flat_map, 0);
rb_define_method(rb_cLazy, "select", lazy_select, 0);
rb_define_method(rb_cLazy, "find_all", lazy_select, 0);
rb_define_method(rb_cLazy, "filter", lazy_select, 0);
rb_define_method(rb_cLazy, "filter_map", lazy_filter_map, 0);
rb_define_method(rb_cLazy, "reject", lazy_reject, 0);
rb_define_method(rb_cLazy, "grep", lazy_grep, 1);
rb_define_method(rb_cLazy, "grep_v", lazy_grep_v, 1);
rb_define_method(rb_cLazy, "zip", lazy_zip, -1);
rb_define_method(rb_cLazy, "take", lazy_take, 1);
rb_define_method(rb_cLazy, "take_while", lazy_take_while, 0);
rb_define_method(rb_cLazy, "drop", lazy_drop, 1);
rb_define_method(rb_cLazy, "drop_while", lazy_drop_while, 0);
rb_define_method(rb_cLazy, "lazy", lazy_lazy, 0);
rb_define_method(rb_cLazy, "chunk", lazy_super, -1);
rb_define_method(rb_cLazy, "slice_before", lazy_super, -1);
rb_define_method(rb_cLazy, "slice_after", lazy_super, -1);
rb_define_method(rb_cLazy, "slice_when", lazy_super, -1);
rb_define_method(rb_cLazy, "chunk_while", lazy_super, -1);
rb_define_method(rb_cLazy, "uniq", lazy_uniq, 0);
rb_define_method(rb_cLazy, "with_index", lazy_with_index, -1);
lazy_use_super_method = rb_hash_new_with_size(18);
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("map")), ID2SYM(rb_intern("_enumerable_map")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("collect")), ID2SYM(rb_intern("_enumerable_collect")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("flat_map")), ID2SYM(rb_intern("_enumerable_flat_map")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("collect_concat")), ID2SYM(rb_intern("_enumerable_collect_concat")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("select")), ID2SYM(rb_intern("_enumerable_select")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("find_all")), ID2SYM(rb_intern("_enumerable_find_all")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("filter")), ID2SYM(rb_intern("_enumerable_filter")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("filter_map")), ID2SYM(rb_intern("_enumerable_filter_map")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("reject")), ID2SYM(rb_intern("_enumerable_reject")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("grep")), ID2SYM(rb_intern("_enumerable_grep")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("grep_v")), ID2SYM(rb_intern("_enumerable_grep_v")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("zip")), ID2SYM(rb_intern("_enumerable_zip")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("take")), ID2SYM(rb_intern("_enumerable_take")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("take_while")), ID2SYM(rb_intern("_enumerable_take_while")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("drop")), ID2SYM(rb_intern("_enumerable_drop")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("drop_while")), ID2SYM(rb_intern("_enumerable_drop_while")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("uniq")), ID2SYM(rb_intern("_enumerable_uniq")));
rb_hash_aset(lazy_use_super_method, ID2SYM(rb_intern("with_index")), ID2SYM(rb_intern("_enumerable_with_index")));
rb_obj_freeze(lazy_use_super_method);
rb_gc_register_mark_object(lazy_use_super_method);
#if 0 /* for RDoc */
rb_define_method(rb_cLazy, "to_a", lazy_to_a, 0);
rb_define_method(rb_cLazy, "chunk", lazy_chunk, 0);
rb_define_method(rb_cLazy, "chunk_while", lazy_chunk_while, 0);
rb_define_method(rb_cLazy, "slice_after", lazy_slice_after, 0);
rb_define_method(rb_cLazy, "slice_before", lazy_slice_before, 0);
rb_define_method(rb_cLazy, "slice_when", lazy_slice_when, 0);
#endif
rb_define_alias(rb_cLazy, "force", "to_a");
rb_eStopIteration = rb_define_class("StopIteration", rb_eIndexError);
rb_define_method(rb_eStopIteration, "result", stop_result, 0);
/* Generator */
rb_cGenerator = rb_define_class_under(rb_cEnumerator, "Generator", rb_cObject);
rb_include_module(rb_cGenerator, rb_mEnumerable);
rb_define_alloc_func(rb_cGenerator, generator_allocate);
rb_define_method(rb_cGenerator, "initialize", generator_initialize, -1);
rb_define_method(rb_cGenerator, "initialize_copy", generator_init_copy, 1);
rb_define_method(rb_cGenerator, "each", generator_each, -1);
/* Yielder */
rb_cYielder = rb_define_class_under(rb_cEnumerator, "Yielder", rb_cObject);
rb_define_alloc_func(rb_cYielder, yielder_allocate);
rb_define_method(rb_cYielder, "initialize", yielder_initialize, 0);
rb_define_method(rb_cYielder, "yield", yielder_yield, -2);
rb_define_method(rb_cYielder, "<<", yielder_yield_push, 1);
rb_define_method(rb_cYielder, "to_proc", yielder_to_proc, 0);
/* Producer */
rb_cEnumProducer = rb_define_class_under(rb_cEnumerator, "Producer", rb_cObject);
rb_define_alloc_func(rb_cEnumProducer, producer_allocate);
rb_define_method(rb_cEnumProducer, "each", producer_each, 0);
rb_define_singleton_method(rb_cEnumerator, "produce", enumerator_s_produce, -1);
/* Chain */
rb_cEnumChain = rb_define_class_under(rb_cEnumerator, "Chain", rb_cEnumerator);
rb_define_alloc_func(rb_cEnumChain, enum_chain_allocate);
rb_define_method(rb_cEnumChain, "initialize", enum_chain_initialize, -2);
rb_define_method(rb_cEnumChain, "initialize_copy", enum_chain_init_copy, 1);
rb_define_method(rb_cEnumChain, "each", enum_chain_each, -1);
rb_define_method(rb_cEnumChain, "size", enum_chain_size, 0);
rb_define_method(rb_cEnumChain, "rewind", enum_chain_rewind, 0);
rb_define_method(rb_cEnumChain, "inspect", enum_chain_inspect, 0);
/* ArithmeticSequence */
rb_cArithSeq = rb_define_class_under(rb_cEnumerator, "ArithmeticSequence", rb_cEnumerator);
rb_undef_alloc_func(rb_cArithSeq);
rb_undef_method(CLASS_OF(rb_cArithSeq), "new");
rb_define_method(rb_cArithSeq, "begin", arith_seq_begin, 0);
rb_define_method(rb_cArithSeq, "end", arith_seq_end, 0);
rb_define_method(rb_cArithSeq, "exclude_end?", arith_seq_exclude_end, 0);
rb_define_method(rb_cArithSeq, "step", arith_seq_step, 0);
rb_define_method(rb_cArithSeq, "first", arith_seq_first, -1);
rb_define_method(rb_cArithSeq, "last", arith_seq_last, -1);
rb_define_method(rb_cArithSeq, "inspect", arith_seq_inspect, 0);
rb_define_method(rb_cArithSeq, "==", arith_seq_eq, 1);
rb_define_method(rb_cArithSeq, "===", arith_seq_eq, 1);
rb_define_method(rb_cArithSeq, "eql?", arith_seq_eq, 1);
rb_define_method(rb_cArithSeq, "hash", arith_seq_hash, 0);
rb_define_method(rb_cArithSeq, "each", arith_seq_each, 0);
rb_define_method(rb_cArithSeq, "size", arith_seq_size, 0);
rb_provide("enumerator.so"); /* for backward compatibility */
}
#undef rb_intern
void
Init_Enumerator(void)
{
id_rewind = rb_intern("rewind");
id_new = rb_intern("new");
id_next = rb_intern("next");
id_result = rb_intern("result");
id_receiver = rb_intern("receiver");
id_arguments = rb_intern("arguments");
id_memo = rb_intern("memo");
id_method = rb_intern("method");
id_force = rb_intern("force");
id_to_enum = rb_intern("to_enum");
id_begin = rb_intern("begin");
id_end = rb_intern("end");
id_step = rb_intern("step");
id_exclude_end = rb_intern("exclude_end");
sym_each = ID2SYM(id_each);
sym_cycle = ID2SYM(rb_intern("cycle"));
sym_yield = ID2SYM(rb_intern("yield"));
InitVM(Enumerator);
}