* lib/pp.rb: rdoced by Sam Roberts.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@8084 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
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akr 2005-03-06 02:55:16 +00:00
parent 25d8e7a119
commit 1b178621c2
2 changed files with 122 additions and 149 deletions

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@ -1,3 +1,7 @@
Sun Mar 6 11:47:10 2005 Sam Roberts <sroberts@uniserve.com>
* lib/pp.rb: rdoced.
Sun Mar 6 11:36:37 2005 Tanaka Akira <akr@m17n.org>
* lib/pp.rb (File::Stat#pretty_print): Etc.getpwuid and Etc.getgrgid

267
lib/pp.rb
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@ -1,150 +1,47 @@
# $Id$
=begin
= Pretty-printer for Ruby objects.
== Which seems better?
non-pretty-printed output by (({p})) is:
#<PP:0x81fedf0 @genspace=#<Proc:0x81feda0>, @group_queue=#<PrettyPrint::GroupQueue:0x81fed3c @queue=[[#<PrettyPrint::Group:0x81fed78 @breakables=[], @depth=0, @break=false>], []]>, @buffer=[], @newline="\n", @group_stack=[#<PrettyPrint::Group:0x81fed78 @breakables=[], @depth=0, @break=false>], @buffer_width=0, @indent=0, @maxwidth=79, @output_width=2, @output=#<IO:0x8114ee4>>
pretty-printed output by (({pp})) is:
#<PP:0x81fedf0
@buffer=[],
@buffer_width=0,
@genspace=#<Proc:0x81feda0>,
@group_queue=
#<PrettyPrint::GroupQueue:0x81fed3c
@queue=
[[#<PrettyPrint::Group:0x81fed78 @break=false, @breakables=[], @depth=0>],
[]]>,
@group_stack=
[#<PrettyPrint::Group:0x81fed78 @break=false, @breakables=[], @depth=0>],
@indent=0,
@maxwidth=79,
@newline="\n",
@output=#<IO:0x8114ee4>,
@output_width=2>
I like the latter. If you do too, this library is for you.
== Usage
: pp(obj)
output ((|obj|)) to (({$>})) in pretty printed format.
It returns (({nil})).
== Output Customization
To define your customized pretty printing function for your classes,
redefine a method (({pretty_print(((|pp|)))})) in the class.
It takes an argument ((|pp|)) which is an instance of the class ((<PP>)).
The method should use PP#text, PP#breakable, PP#nest, PP#group and
PP#pp to print the object.
= PP
== super class
((<PrettyPrint>))
== class methods
--- PP.pp(obj[, out[, width]])
outputs ((|obj|)) to ((|out|)) in pretty printed format of
((|width|)) columns in width.
If ((|out|)) is omitted, (({$>})) is assumed.
If ((|width|)) is omitted, 79 is assumed.
PP.pp returns ((|out|)).
--- PP.singleline_pp(obj[, out])
outputs ((|obj|)) to ((|out|)) like (({PP.pp})) but with no indent and
newline.
PP.singleline_pp returns ((|out|)).
--- PP.sharing_detection
returns the sharing detection flag as a boolean value.
It is false by default.
--- PP.sharing_detection = boolean_value
sets the sharing detection flag.
== methods
--- pp(obj)
adds ((|obj|)) to the pretty printing buffer
using Object#pretty_print or Object#pretty_print_cycle.
Object#pretty_print_cycle is used when ((|obj|)) is already
printed, a.k.a the object reference chain has a cycle.
--- object_group(obj) { ... }
is a convenience method which is same as follows:
group(1, '#<' + obj.class.name, '>') { ... }
--- comma_breakable
is a convenience method which is same as follows:
text ','
breakable
--- seplist(list[, separator_proc[, iter_method]]) {|elt| ... }
adds a separated list.
The list is separated by comma with breakable space, by default.
seplist iterates the ((|list|)) using ((|iter_method|)).
It yields each object to the block given for seplist.
The procedure ((|separator_proc|)) is called between each yields.
If the iteration is zero times, ((|separator_proc|)) is not called at all.
If ((|separator_proc|)) is nil or not given,
(({lambda { comma_breakable }})) is used.
If ((|iter_method|)) is not given, (({:each})) is used.
For example, following 3 code fragments has similar effect.
q.seplist([1,2,3]) {|v| xxx v }
q.seplist([1,2,3], lambda { comma_breakable }, :each) {|v| xxx v }
xxx 1
q.comma_breakable
xxx 2
q.comma_breakable
xxx 3
= Object
--- pretty_print(pp)
is a default pretty printing method for general objects.
It calls (({pretty_print_instance_variables})) to list instance variables.
If (({self})) has a customized (redefined) (({inspect})) method,
the result of (({self.inspect})) is used but it obviously has no
line break hints.
This module provides predefined pretty_print() methods for some of
the most commonly used built-in classes for convenience.
--- pretty_print_cycle(pp)
is a default pretty printing method for general objects that are
detected as part of a cycle.
--- pretty_print_instance_variables
returns a sorted array of instance variable names.
This method should return an array of names of instance variables as symbols or strings as:
(({[:@a, :@b]})).
--- pretty_print_inspect
is (({inspect})) implementation using (({pretty_print})).
If you implement (({pretty_print})), it can be used as follows.
alias inspect pretty_print_inspect
== AUTHOR
Tanaka Akira <akr@m17n.org>
=end
# == Pretty-printer for Ruby objects.
#
# = Which seems better?
#
# non-pretty-printed output by #p is:
# #<PP:0x81fedf0 @genspace=#<Proc:0x81feda0>, @group_queue=#<PrettyPrint::GroupQueue:0x81fed3c @queue=[[#<PrettyPrint::Group:0x81fed78 @breakables=[], @depth=0, @break=false>], []]>, @buffer=[], @newline="\n", @group_stack=[#<PrettyPrint::Group:0x81fed78 @breakables=[], @depth=0, @break=false>], @buffer_width=0, @indent=0, @maxwidth=79, @output_width=2, @output=#<IO:0x8114ee4>>
#
# pretty-printed output by #pp is:
# #<PP:0x81fedf0
# @buffer=[],
# @buffer_width=0,
# @genspace=#<Proc:0x81feda0>,
# @group_queue=
# #<PrettyPrint::GroupQueue:0x81fed3c
# @queue=
# [[#<PrettyPrint::Group:0x81fed78 @break=false, @breakables=[], @depth=0>],
# []]>,
# @group_stack=
# [#<PrettyPrint::Group:0x81fed78 @break=false, @breakables=[], @depth=0>],
# @indent=0,
# @maxwidth=79,
# @newline="\n",
# @output=#<IO:0x8114ee4>,
# @output_width=2>
#
# I like the latter. If you do too, this library is for you.
#
# = Usage
#
# pp(obj)
#
# output +obj+ to +$>+ in pretty printed format.
#
# It returns +nil+.
#
# = Output Customization
# To define your customized pretty printing function for your classes,
# redefine a method #pretty_print(+pp+) in the class.
# It takes an argument +pp+ which is an instance of the class PP.
# The method should use PP#text, PP#breakable, PP#nest, PP#group and
# PP#pp to print the object.
#
# = Author
# Tanaka Akira <akr@m17n.org>
require 'prettyprint'
@ -160,6 +57,13 @@ module Kernel
end
class PP < PrettyPrint
# Outputs +obj+ to +out+ in pretty printed format of
# +width+ columns in width.
#
# If +out+ is omitted, +$>+ is assumed.
# If +width+ is omitted, 79 is assumed.
#
# PP.pp returns +out+.
def PP.pp(obj, out=$>, width=79)
q = PP.new(out, width)
q.guard_inspect_key {q.pp obj}
@ -168,6 +72,10 @@ class PP < PrettyPrint
out << "\n"
end
# Outputs +obj+ to +out+ like PP.pp but with no indent and
# newline.
#
# PP.singleline_pp returns +out+.
def PP.singleline_pp(obj, out=$>)
q = SingleLine.new(out)
q.guard_inspect_key {q.pp obj}
@ -177,6 +85,8 @@ class PP < PrettyPrint
@sharing_detection = false
class << self
# Returns the sharing detection flag as a boolean value.
# It is false by default.
attr_accessor :sharing_detection
end
@ -198,6 +108,11 @@ class PP < PrettyPrint
end
end
# Adds +obj+ to the pretty printing buffer
# using Object#pretty_print or Object#pretty_print_cycle.
#
# Object#pretty_print_cycle is used when +obj+ is already
# printed, a.k.a the object reference chain has a cycle.
def pp(obj)
id = obj.__id__
@ -214,7 +129,10 @@ class PP < PrettyPrint
end
end
def object_group(obj, &block)
# A convenience method which is same as follows:
#
# group(1, '#<' + obj.class.name, '>') { ... }
def object_group(obj, &block) # :yield:
group(1, '#<' + obj.class.name, '>', &block)
end
@ -224,12 +142,40 @@ class PP < PrettyPrint
group(1, "\#<#{obj.class}:0x#{id}", '>', &block)
end
# A convenience method which is same as follows:
#
# text ','
# breakable
def comma_breakable
text ','
breakable
end
def seplist(list, sep=nil, iter_method=:each)
# Adds a separated list.
# The list is separated by comma with breakable space, by default.
#
# #seplist iterates the +list+ using +iter_method+.
# It yields each object to the block given for #seplist.
# The procedure +separator_proc+ is called between each yields.
#
# If the iteration is zero times, +separator_proc+ is not called at all.
#
# If +separator_proc+ is nil or not given,
# +lambda { comma_breakable }+ is used.
# If +iter_method+ is not given, :each is used.
#
# For example, following 3 code fragments has similar effect.
#
# q.seplist([1,2,3]) {|v| xxx v }
#
# q.seplist([1,2,3], lambda { comma_breakable }, :each) {|v| xxx v }
#
# xxx 1
# q.comma_breakable
# xxx 2
# q.comma_breakable
# xxx 3
def seplist(list, sep=nil, iter_method=:each) # :yield: element
sep ||= lambda { comma_breakable }
first = true
list.__send__(iter_method) {|*v|
@ -285,6 +231,15 @@ class PP < PrettyPrint
# 3. specific to_s if instance variable is empty
# 4. generic pretty_print
# A default pretty printing method for general objects.
# It calls #pretty_print_instance_variables to list instance variables.
#
# If +self+ has a customized (redefined) #inspect method,
# the result of self.inspect is used but it obviously has no
# line break hints.
#
# This module provides predefined #pretty_print methods for some of
# the most commonly used built-in classes for convenience.
def pretty_print(q)
if /\(Kernel\)#/ !~ method(:inspect).inspect
q.text self.inspect
@ -295,6 +250,8 @@ class PP < PrettyPrint
end
end
# A default pretty printing method for general objects that are
# detected as part of a cycle.
def pretty_print_cycle(q)
q.object_address_group(self) {
q.breakable
@ -302,10 +259,21 @@ class PP < PrettyPrint
}
end
# Returns a sorted array of instance variable names.
#
# This method should return an array of names of instance variables as symbols or strings as:
# +[:@a, :@b]+.
def pretty_print_instance_variables
instance_variables.sort
end
# Is #inspect implementation using #pretty_print.
# If you implement #pretty_print, it can be used as follows.
#
# alias inspect pretty_print_inspect
#
# However, doing this requires that every class that #inspect is called on
# implement #pretty_print, or a RuntimeError will be raised.
def pretty_print_inspect
if /\(PP::ObjectMixin\)#/ =~ method(:pretty_print).inspect
raise "pretty_print is not overridden."
@ -488,6 +456,7 @@ end
}
}
# :enddoc:
if __FILE__ == $0
require 'test/unit'