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ruby--ruby/lib/erb.rb

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Ruby

# -*- coding: us-ascii -*-
# frozen_string_literal: true
# = ERB -- Ruby Templating
#
# Author:: Masatoshi SEKI
# Documentation:: James Edward Gray II, Gavin Sinclair, and Simon Chiang
#
# See ERB for primary documentation and ERB::Util for a couple of utility
# routines.
#
# Copyright (c) 1999-2000,2002,2003 Masatoshi SEKI
#
# You can redistribute it and/or modify it under the same terms as Ruby.
require 'cgi/util'
require 'erb/version'
#
# = ERB -- Ruby Templating
#
# == Introduction
#
# ERB provides an easy to use but powerful templating system for Ruby. Using
# ERB, actual Ruby code can be added to any plain text document for the
# purposes of generating document information details and/or flow control.
#
# A very simple example is this:
#
# require 'erb'
#
# x = 42
# template = ERB.new <<-EOF
# The value of x is: <%= x %>
# EOF
# puts template.result(binding)
#
# <em>Prints:</em> The value of x is: 42
#
# More complex examples are given below.
#
#
# == Recognized Tags
#
# ERB recognizes certain tags in the provided template and converts them based
# on the rules below:
#
# <% Ruby code -- inline with output %>
# <%= Ruby expression -- replace with result %>
# <%# comment -- ignored -- useful in testing %> (`<% #` doesn't work. Don't use Ruby comments.)
# % a line of Ruby code -- treated as <% line %> (optional -- see ERB.new)
# %% replaced with % if first thing on a line and % processing is used
# <%% or %%> -- replace with <% or %> respectively
#
# All other text is passed through ERB filtering unchanged.
#
#
# == Options
#
# There are several settings you can change when you use ERB:
# * the nature of the tags that are recognized;
# * the binding used to resolve local variables in the template.
#
# See the ERB.new and ERB#result methods for more detail.
#
# == Character encodings
#
# ERB (or Ruby code generated by ERB) returns a string in the same
# character encoding as the input string. When the input string has
# a magic comment, however, it returns a string in the encoding specified
# by the magic comment.
#
# # -*- coding: utf-8 -*-
# require 'erb'
#
# template = ERB.new <<EOF
# <%#-*- coding: Big5 -*-%>
# \_\_ENCODING\_\_ is <%= \_\_ENCODING\_\_ %>.
# EOF
# puts template.result
#
# <em>Prints:</em> \_\_ENCODING\_\_ is Big5.
#
#
# == Examples
#
# === Plain Text
#
# ERB is useful for any generic templating situation. Note that in this example, we use the
# convenient "% at start of line" tag, and we quote the template literally with
# <tt>%q{...}</tt> to avoid trouble with the backslash.
#
# require "erb"
#
# # Create template.
# template = %q{
# From: James Edward Gray II <james@grayproductions.net>
# To: <%= to %>
# Subject: Addressing Needs
#
# <%= to[/\w+/] %>:
#
# Just wanted to send a quick note assuring that your needs are being
# addressed.
#
# I want you to know that my team will keep working on the issues,
# especially:
#
# <%# ignore numerous minor requests -- focus on priorities %>
# % priorities.each do |priority|
# * <%= priority %>
# % end
#
# Thanks for your patience.
#
# James Edward Gray II
# }.gsub(/^ /, '')
#
# message = ERB.new(template, trim_mode: "%<>")
#
# # Set up template data.
# to = "Community Spokesman <spokesman@ruby_community.org>"
# priorities = [ "Run Ruby Quiz",
# "Document Modules",
# "Answer Questions on Ruby Talk" ]
#
# # Produce result.
# email = message.result
# puts email
#
# <i>Generates:</i>
#
# From: James Edward Gray II <james@grayproductions.net>
# To: Community Spokesman <spokesman@ruby_community.org>
# Subject: Addressing Needs
#
# Community:
#
# Just wanted to send a quick note assuring that your needs are being addressed.
#
# I want you to know that my team will keep working on the issues, especially:
#
# * Run Ruby Quiz
# * Document Modules
# * Answer Questions on Ruby Talk
#
# Thanks for your patience.
#
# James Edward Gray II
#
# === Ruby in HTML
#
# ERB is often used in <tt>.rhtml</tt> files (HTML with embedded Ruby). Notice the need in
# this example to provide a special binding when the template is run, so that the instance
# variables in the Product object can be resolved.
#
# require "erb"
#
# # Build template data class.
# class Product
# def initialize( code, name, desc, cost )
# @code = code
# @name = name
# @desc = desc
# @cost = cost
#
# @features = [ ]
# end
#
# def add_feature( feature )
# @features << feature
# end
#
# # Support templating of member data.
# def get_binding
# binding
# end
#
# # ...
# end
#
# # Create template.
# template = %{
# <html>
# <head><title>Ruby Toys -- <%= @name %></title></head>
# <body>
#
# <h1><%= @name %> (<%= @code %>)</h1>
# <p><%= @desc %></p>
#
# <ul>
# <% @features.each do |f| %>
# <li><b><%= f %></b></li>
# <% end %>
# </ul>
#
# <p>
# <% if @cost < 10 %>
# <b>Only <%= @cost %>!!!</b>
# <% else %>
# Call for a price, today!
# <% end %>
# </p>
#
# </body>
# </html>
# }.gsub(/^ /, '')
#
# rhtml = ERB.new(template)
#
# # Set up template data.
# toy = Product.new( "TZ-1002",
# "Rubysapien",
# "Geek's Best Friend! Responds to Ruby commands...",
# 999.95 )
# toy.add_feature("Listens for verbal commands in the Ruby language!")
# toy.add_feature("Ignores Perl, Java, and all C variants.")
# toy.add_feature("Karate-Chop Action!!!")
# toy.add_feature("Matz signature on left leg.")
# toy.add_feature("Gem studded eyes... Rubies, of course!")
#
# # Produce result.
# rhtml.run(toy.get_binding)
#
# <i>Generates (some blank lines removed):</i>
#
# <html>
# <head><title>Ruby Toys -- Rubysapien</title></head>
# <body>
#
# <h1>Rubysapien (TZ-1002)</h1>
# <p>Geek's Best Friend! Responds to Ruby commands...</p>
#
# <ul>
# <li><b>Listens for verbal commands in the Ruby language!</b></li>
# <li><b>Ignores Perl, Java, and all C variants.</b></li>
# <li><b>Karate-Chop Action!!!</b></li>
# <li><b>Matz signature on left leg.</b></li>
# <li><b>Gem studded eyes... Rubies, of course!</b></li>
# </ul>
#
# <p>
# Call for a price, today!
# </p>
#
# </body>
# </html>
#
#
# == Notes
#
# There are a variety of templating solutions available in various Ruby projects.
# For example, RDoc, distributed with Ruby, uses its own template engine, which
# can be reused elsewhere.
#
# Other popular engines could be found in the corresponding
# {Category}[https://www.ruby-toolbox.com/categories/template_engines] of
# The Ruby Toolbox.
#
class ERB
Revision = '$Date:: $' # :nodoc: #'
deprecate_constant :Revision
# Returns revision information for the erb.rb module.
def self.version
VERSION
end
end
#--
# ERB::Compiler
class ERB
# = ERB::Compiler
#
# Compiles ERB templates into Ruby code; the compiled code produces the
# template result when evaluated. ERB::Compiler provides hooks to define how
# generated output is handled.
#
# Internally ERB does something like this to generate the code returned by
# ERB#src:
#
# compiler = ERB::Compiler.new('<>')
# compiler.pre_cmd = ["_erbout=+''"]
# compiler.put_cmd = "_erbout.<<"
# compiler.insert_cmd = "_erbout.<<"
# compiler.post_cmd = ["_erbout"]
#
# code, enc = compiler.compile("Got <%= obj %>!\n")
# puts code
#
# <i>Generates</i>:
#
# #coding:UTF-8
# _erbout=+''; _erbout.<< "Got ".freeze; _erbout.<<(( obj ).to_s); _erbout.<< "!\n".freeze; _erbout
#
# By default the output is sent to the print method. For example:
#
# compiler = ERB::Compiler.new('<>')
# code, enc = compiler.compile("Got <%= obj %>!\n")
# puts code
#
# <i>Generates</i>:
#
# #coding:UTF-8
# print "Got ".freeze; print(( obj ).to_s); print "!\n".freeze
#
# == Evaluation
#
# The compiled code can be used in any context where the names in the code
# correctly resolve. Using the last example, each of these print 'Got It!'
#
# Evaluate using a variable:
#
# obj = 'It'
# eval code
#
# Evaluate using an input:
#
# mod = Module.new
# mod.module_eval %{
# def get(obj)
# #{code}
# end
# }
# extend mod
# get('It')
#
# Evaluate using an accessor:
#
# klass = Class.new Object
# klass.class_eval %{
# attr_accessor :obj
# def initialize(obj)
# @obj = obj
# end
# def get_it
# #{code}
# end
# }
# klass.new('It').get_it
#
# Good! See also ERB#def_method, ERB#def_module, and ERB#def_class.
class Compiler # :nodoc:
class PercentLine # :nodoc:
def initialize(str)
@value = str
end
attr_reader :value
alias :to_s :value
end
class Scanner # :nodoc:
@scanner_map = {}
class << self
def register_scanner(klass, trim_mode, percent)
@scanner_map[[trim_mode, percent]] = klass
end
alias :regist_scanner :register_scanner
end
def self.default_scanner=(klass)
@default_scanner = klass
end
def self.make_scanner(src, trim_mode, percent)
klass = @scanner_map.fetch([trim_mode, percent], @default_scanner)
klass.new(src, trim_mode, percent)
end
DEFAULT_STAGS = %w(<%% <%= <%# <%).freeze
DEFAULT_ETAGS = %w(%%> %>).freeze
def initialize(src, trim_mode, percent)
@src = src
@stag = nil
@stags = DEFAULT_STAGS
@etags = DEFAULT_ETAGS
end
attr_accessor :stag
attr_reader :stags, :etags
def scan; end
end
class TrimScanner < Scanner # :nodoc:
def initialize(src, trim_mode, percent)
super
@trim_mode = trim_mode
@percent = percent
if @trim_mode == '>'
@scan_reg = /(.*?)(%>\r?\n|#{(stags + etags).join('|')}|\n|\z)/m
@scan_line = self.method(:trim_line1)
elsif @trim_mode == '<>'
@scan_reg = /(.*?)(%>\r?\n|#{(stags + etags).join('|')}|\n|\z)/m
@scan_line = self.method(:trim_line2)
elsif @trim_mode == '-'
@scan_reg = /(.*?)(^[ \t]*<%\-|<%\-|-%>\r?\n|-%>|#{(stags + etags).join('|')}|\z)/m
@scan_line = self.method(:explicit_trim_line)
else
@scan_reg = /(.*?)(#{(stags + etags).join('|')}|\n|\z)/m
@scan_line = self.method(:scan_line)
end
end
def scan(&block)
@stag = nil
if @percent
@src.each_line do |line|
percent_line(line, &block)
end
else
@scan_line.call(@src, &block)
end
nil
end
def percent_line(line, &block)
if @stag || line[0] != ?%
return @scan_line.call(line, &block)
end
line[0] = ''
if line[0] == ?%
@scan_line.call(line, &block)
else
yield(PercentLine.new(line.chomp))
end
end
def scan_line(line)
line.scan(@scan_reg) do |tokens|
tokens.each do |token|
next if token.empty?
yield(token)
end
end
end
def trim_line1(line)
line.scan(@scan_reg) do |tokens|
tokens.each do |token|
next if token.empty?
if token == "%>\n" || token == "%>\r\n"
yield('%>')
yield(:cr)
else
yield(token)
end
end
end
end
def trim_line2(line)
head = nil
line.scan(@scan_reg) do |tokens|
tokens.each do |token|
next if token.empty?
head = token unless head
if token == "%>\n" || token == "%>\r\n"
yield('%>')
if is_erb_stag?(head)
yield(:cr)
else
yield("\n")
end
head = nil
else
yield(token)
head = nil if token == "\n"
end
end
end
end
def explicit_trim_line(line)
line.scan(@scan_reg) do |tokens|
tokens.each do |token|
next if token.empty?
if @stag.nil? && /[ \t]*<%-/ =~ token
yield('<%')
elsif @stag && (token == "-%>\n" || token == "-%>\r\n")
yield('%>')
yield(:cr)
elsif @stag && token == '-%>'
yield('%>')
else
yield(token)
end
end
end
end
ERB_STAG = %w(<%= <%# <%)
def is_erb_stag?(s)
ERB_STAG.member?(s)
end
end
Scanner.default_scanner = TrimScanner
begin
require 'strscan'
rescue LoadError
else
class SimpleScanner < Scanner # :nodoc:
def scan
stag_reg = (stags == DEFAULT_STAGS) ? /(.*?)(<%[%=#]?|\z)/m : /(.*?)(#{stags.join('|')}|\z)/m
etag_reg = (etags == DEFAULT_ETAGS) ? /(.*?)(%%?>|\z)/m : /(.*?)(#{etags.join('|')}|\z)/m
scanner = StringScanner.new(@src)
while ! scanner.eos?
scanner.scan(@stag ? etag_reg : stag_reg)
yield(scanner[1])
yield(scanner[2])
end
end
end
Scanner.register_scanner(SimpleScanner, nil, false)
class ExplicitScanner < Scanner # :nodoc:
def scan
stag_reg = /(.*?)(^[ \t]*<%-|<%-|#{stags.join('|')}|\z)/m
etag_reg = /(.*?)(-%>|#{etags.join('|')}|\z)/m
scanner = StringScanner.new(@src)
while ! scanner.eos?
scanner.scan(@stag ? etag_reg : stag_reg)
yield(scanner[1])
elem = scanner[2]
if /[ \t]*<%-/ =~ elem
yield('<%')
elsif elem == '-%>'
yield('%>')
yield(:cr) if scanner.scan(/(\r?\n|\z)/)
else
yield(elem)
end
end
end
end
Scanner.register_scanner(ExplicitScanner, '-', false)
end
class Buffer # :nodoc:
def initialize(compiler, enc=nil, frozen=nil)
@compiler = compiler
@line = []
@script = +''
@script << "#coding:#{enc}\n" if enc
@script << "#frozen-string-literal:#{frozen}\n" unless frozen.nil?
@compiler.pre_cmd.each do |x|
push(x)
end
end
attr_reader :script
def push(cmd)
@line << cmd
end
def cr
@script << (@line.join('; '))
@line = []
@script << "\n"
end
def close
return unless @line
@compiler.post_cmd.each do |x|
push(x)
end
@script << (@line.join('; '))
@line = nil
end
end
def add_put_cmd(out, content)
out.push("#{@put_cmd} #{content.dump}.freeze#{"\n" * content.count("\n")}")
end
def add_insert_cmd(out, content)
out.push("#{@insert_cmd}((#{content}).to_s)")
end
# Compiles an ERB template into Ruby code. Returns an array of the code
# and encoding like ["code", Encoding].
def compile(s)
enc = s.encoding
raise ArgumentError, "#{enc} is not ASCII compatible" if enc.dummy?
s = s.b # see String#b
magic_comment = detect_magic_comment(s, enc)
out = Buffer.new(self, *magic_comment)
self.content = +''
scanner = make_scanner(s)
scanner.scan do |token|
next if token.nil?
next if token == ''
if scanner.stag.nil?
compile_stag(token, out, scanner)
else
compile_etag(token, out, scanner)
end
end
add_put_cmd(out, content) if content.size > 0
out.close
return out.script, *magic_comment
end
def compile_stag(stag, out, scanner)
case stag
when PercentLine
add_put_cmd(out, content) if content.size > 0
self.content = +''
out.push(stag.to_s)
out.cr
when :cr
out.cr
when '<%', '<%=', '<%#'
scanner.stag = stag
add_put_cmd(out, content) if content.size > 0
self.content = +''
when "\n"
content << "\n"
add_put_cmd(out, content)
self.content = +''
when '<%%'
content << '<%'
else
content << stag
end
end
def compile_etag(etag, out, scanner)
case etag
when '%>'
compile_content(scanner.stag, out)
scanner.stag = nil
self.content = +''
when '%%>'
content << '%>'
else
content << etag
end
end
def compile_content(stag, out)
case stag
when '<%'
if content[-1] == ?\n
content.chop!
out.push(content)
out.cr
else
out.push(content)
end
when '<%='
add_insert_cmd(out, content)
when '<%#'
# commented out
end
end
def prepare_trim_mode(mode) # :nodoc:
case mode
when 1
return [false, '>']
when 2
return [false, '<>']
when 0, nil
return [false, nil]
when String
unless mode.match?(/\A(%|-|>|<>){1,2}\z/)
warn_invalid_trim_mode(mode, uplevel: 5)
end
perc = mode.include?('%')
if mode.include?('-')
return [perc, '-']
elsif mode.include?('<>')
return [perc, '<>']
elsif mode.include?('>')
return [perc, '>']
else
[perc, nil]
end
else
warn_invalid_trim_mode(mode, uplevel: 5)
return [false, nil]
end
end
def make_scanner(src) # :nodoc:
Scanner.make_scanner(src, @trim_mode, @percent)
end
# Construct a new compiler using the trim_mode. See ERB::new for available
# trim modes.
def initialize(trim_mode)
@percent, @trim_mode = prepare_trim_mode(trim_mode)
@put_cmd = 'print'
@insert_cmd = @put_cmd
@pre_cmd = []
@post_cmd = []
end
attr_reader :percent, :trim_mode
# The command to handle text that ends with a newline
attr_accessor :put_cmd
# The command to handle text that is inserted prior to a newline
attr_accessor :insert_cmd
# An array of commands prepended to compiled code
attr_accessor :pre_cmd
# An array of commands appended to compiled code
attr_accessor :post_cmd
private
# A buffered text in #compile
attr_accessor :content
def detect_magic_comment(s, enc = nil)
re = @percent ? /\G(?:<%#(.*)%>|%#(.*)\n)/ : /\G<%#(.*)%>/
frozen = nil
s.scan(re) do
comment = $+
comment = $1 if comment[/-\*-\s*([^\s].*?)\s*-\*-$/]
case comment
when %r"coding\s*[=:]\s*([[:alnum:]\-_]+)"
enc = Encoding.find($1.sub(/-(?:mac|dos|unix)/i, ''))
when %r"frozen[-_]string[-_]literal\s*:\s*([[:alnum:]]+)"
frozen = $1
end
end
return enc, frozen
end
def warn_invalid_trim_mode(mode, uplevel:)
warn "Invalid ERB trim mode: #{mode.inspect} (trim_mode: nil, 0, 1, 2, or String composed of '%' and/or '-', '>', '<>')", uplevel: uplevel + 1
end
end
end
#--
# ERB
class ERB
#
# Constructs a new ERB object with the template specified in _str_.
#
# An ERB object works by building a chunk of Ruby code that will output
# the completed template when run.
#
# If _trim_mode_ is passed a String containing one or more of the following
# modifiers, ERB will adjust its code generation as listed:
#
# % enables Ruby code processing for lines beginning with %
# <> omit newline for lines starting with <% and ending in %>
# > omit newline for lines ending in %>
# - omit blank lines ending in -%>
#
# _eoutvar_ can be used to set the name of the variable ERB will build up
# its output in. This is useful when you need to run multiple ERB
# templates through the same binding and/or when you want to control where
# output ends up. Pass the name of the variable to be used inside a String.
#
# === Example
#
# require "erb"
#
# # build data class
# class Listings
# PRODUCT = { :name => "Chicken Fried Steak",
# :desc => "A well messages pattie, breaded and fried.",
# :cost => 9.95 }
#
# attr_reader :product, :price
#
# def initialize( product = "", price = "" )
# @product = product
# @price = price
# end
#
# def build
# b = binding
# # create and run templates, filling member data variables
# ERB.new(<<-'END_PRODUCT'.gsub(/^\s+/, ""), trim_mode: "", eoutvar: "@product").result b
# <%= PRODUCT[:name] %>
# <%= PRODUCT[:desc] %>
# END_PRODUCT
# ERB.new(<<-'END_PRICE'.gsub(/^\s+/, ""), trim_mode: "", eoutvar: "@price").result b
# <%= PRODUCT[:name] %> -- <%= PRODUCT[:cost] %>
# <%= PRODUCT[:desc] %>
# END_PRICE
# end
# end
#
# # setup template data
# listings = Listings.new
# listings.build
#
# puts listings.product + "\n" + listings.price
#
# _Generates_
#
# Chicken Fried Steak
# A well messages pattie, breaded and fried.
#
# Chicken Fried Steak -- 9.95
# A well messages pattie, breaded and fried.
#
def initialize(str, trim_mode: nil, eoutvar: '_erbout')
compiler = make_compiler(trim_mode)
set_eoutvar(compiler, eoutvar)
@src, @encoding, @frozen_string = *compiler.compile(str)
@filename = nil
@lineno = 0
@_init = self.class.singleton_class
end
NOT_GIVEN = Object.new
private_constant :NOT_GIVEN
##
# Creates a new compiler for ERB. See ERB::Compiler.new for details
def make_compiler(trim_mode)
ERB::Compiler.new(trim_mode)
end
# The Ruby code generated by ERB
attr_reader :src
# The encoding to eval
attr_reader :encoding
# The optional _filename_ argument passed to Kernel#eval when the ERB code
# is run
attr_accessor :filename
# The optional _lineno_ argument passed to Kernel#eval when the ERB code
# is run
attr_accessor :lineno
#
# Sets optional filename and line number that will be used in ERB code
# evaluation and error reporting. See also #filename= and #lineno=
#
# erb = ERB.new('<%= some_x %>')
# erb.render
# # undefined local variable or method `some_x'
# # from (erb):1
#
# erb.location = ['file.erb', 3]
# # All subsequent error reporting would use new location
# erb.render
# # undefined local variable or method `some_x'
# # from file.erb:4
#
def location=((filename, lineno))
@filename = filename
@lineno = lineno if lineno
end
#
# Can be used to set _eoutvar_ as described in ERB::new. It's probably
# easier to just use the constructor though, since calling this method
# requires the setup of an ERB _compiler_ object.
#
def set_eoutvar(compiler, eoutvar = '_erbout')
compiler.put_cmd = "#{eoutvar}.<<"
compiler.insert_cmd = "#{eoutvar}.<<"
compiler.pre_cmd = ["#{eoutvar} = +''"]
compiler.post_cmd = [eoutvar]
end
# Generate results and print them. (see ERB#result)
def run(b=new_toplevel)
print self.result(b)
end
#
# Executes the generated ERB code to produce a completed template, returning
# the results of that code. (See ERB::new for details on how this process
# can be affected by _safe_level_.)
#
# _b_ accepts a Binding object which is used to set the context of
# code evaluation.
#
def result(b=new_toplevel)
unless @_init.equal?(self.class.singleton_class)
raise ArgumentError, "not initialized"
end
eval(@src, b, (@filename || '(erb)'), @lineno)
end
# Render a template on a new toplevel binding with local variables specified
# by a Hash object.
def result_with_hash(hash)
b = new_toplevel(hash.keys)
hash.each_pair do |key, value|
b.local_variable_set(key, value)
end
result(b)
end
##
# Returns a new binding each time *near* TOPLEVEL_BINDING for runs that do
# not specify a binding.
def new_toplevel(vars = nil)
b = TOPLEVEL_BINDING
if vars
vars = vars.select {|v| b.local_variable_defined?(v)}
unless vars.empty?
return b.eval("tap {|;#{vars.join(',')}| break binding}")
end
end
b.dup
end
private :new_toplevel
# Define _methodname_ as instance method of _mod_ from compiled Ruby source.
#
# example:
# filename = 'example.rhtml' # 'arg1' and 'arg2' are used in example.rhtml
# erb = ERB.new(File.read(filename))
# erb.def_method(MyClass, 'render(arg1, arg2)', filename)
# print MyClass.new.render('foo', 123)
def def_method(mod, methodname, fname='(ERB)')
src = self.src.sub(/^(?!#|$)/) {"def #{methodname}\n"} << "\nend\n"
mod.module_eval do
eval(src, binding, fname, -1)
end
end
# Create unnamed module, define _methodname_ as instance method of it, and return it.
#
# example:
# filename = 'example.rhtml' # 'arg1' and 'arg2' are used in example.rhtml
# erb = ERB.new(File.read(filename))
# erb.filename = filename
# MyModule = erb.def_module('render(arg1, arg2)')
# class MyClass
# include MyModule
# end
def def_module(methodname='erb')
mod = Module.new
def_method(mod, methodname, @filename || '(ERB)')
mod
end
# Define unnamed class which has _methodname_ as instance method, and return it.
#
# example:
# class MyClass_
# def initialize(arg1, arg2)
# @arg1 = arg1; @arg2 = arg2
# end
# end
# filename = 'example.rhtml' # @arg1 and @arg2 are used in example.rhtml
# erb = ERB.new(File.read(filename))
# erb.filename = filename
# MyClass = erb.def_class(MyClass_, 'render()')
# print MyClass.new('foo', 123).render()
def def_class(superklass=Object, methodname='result')
cls = Class.new(superklass)
def_method(cls, methodname, @filename || '(ERB)')
cls
end
end
#--
# ERB::Util
class ERB
# A utility module for conversion routines, often handy in HTML generation.
module Util
public
#
# A utility method for escaping HTML tag characters in _s_.
#
# require "erb"
# include ERB::Util
#
# puts html_escape("is a > 0 & a < 10?")
#
# _Generates_
#
# is a &gt; 0 &amp; a &lt; 10?
#
def html_escape(s)
CGI.escapeHTML(s.to_s)
end
alias h html_escape
module_function :h
module_function :html_escape
#
# A utility method for encoding the String _s_ as a URL.
#
# require "erb"
# include ERB::Util
#
# puts url_encode("Programming Ruby: The Pragmatic Programmer's Guide")
#
# _Generates_
#
# Programming%20Ruby%3A%20%20The%20Pragmatic%20Programmer%27s%20Guide
#
def url_encode(s)
s.to_s.b.gsub(/[^a-zA-Z0-9_\-.~]/n) { |m|
sprintf("%%%02X", m.unpack1("C"))
}
end
alias u url_encode
module_function :u
module_function :url_encode
end
end
#--
# ERB::DefMethod
class ERB
# Utility module to define eRuby script as instance method.
#
# === Example
#
# example.rhtml:
# <% for item in @items %>
# <b><%= item %></b>
# <% end %>
#
# example.rb:
# require 'erb'
# class MyClass
# extend ERB::DefMethod
# def_erb_method('render()', 'example.rhtml')
# def initialize(items)
# @items = items
# end
# end
# print MyClass.new([10,20,30]).render()
#
# result:
#
# <b>10</b>
#
# <b>20</b>
#
# <b>30</b>
#
module DefMethod
public
# define _methodname_ as instance method of current module, using ERB
# object or eRuby file
def def_erb_method(methodname, erb_or_fname)
if erb_or_fname.kind_of? String
fname = erb_or_fname
erb = ERB.new(File.read(fname))
erb.def_method(self, methodname, fname)
else
erb = erb_or_fname
erb.def_method(self, methodname, erb.filename || '(ERB)')
end
end
module_function :def_erb_method
end
end