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$:.unshift File.dirname(__FILE__) + "/../lib"
require 'pp'
require "parslet"
# Demonstrates modular parsers, split out over many classes. Please look at
# ip_address.rb as well.
module ALanguage
include Parslet
# Parslet rules are really a special kind of method. Mix them into your
# classes!
rule(:a_language) { str('aaa') }
end
# Parslet parsers are parslet atoms as well. Create an instance and chain them
# to your other rules.
#
class BLanguage < Parslet::Parser
root :blang
rule(:blang) { str('bbb') }
end
# Parslet atoms are really Ruby values, pass them around.
c_language = Parslet.str('ccc')
class Language < Parslet::Parser
def initialize(c_language)
@c_language = c_language
super()
end
root :root
include ALanguage
rule(:root) { str('a(') >> a_language >> str(')') >> space |
str('b(') >> BLanguage.new >> str(')') >> space |
str('c(') >> @c_language >> str(')') >> space }
rule(:space) { str(' ').maybe }
end
Language.new(c_language).parse('a(aaa)')
Language.new(c_language).parse('b(bbb)')
Language.new(c_language).parse('c(ccc)')
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