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# The base class for all your parsers. Use as follows:
#
# require 'parslet'
#
# class MyParser < Parslet::Parser
# rule(:a) { str('a').repeat }
# root(:a)
# end
#
# pp MyParser.new.parse('aaaa') # => 'aaaa'
# pp MyParser.new.parse('bbbb') # => Parslet::Atoms::ParseFailed:
# # Don't know what to do with bbbb at line 1 char 1.
#
# Parslet::Parser is also a grammar atom. This means that you can mix full
# fledged parsers freely with small parts of a different parser.
#
# Example:
# class ParserA < Parslet::Parser
# root :aaa
# rule(:aaa) { str('a').repeat(3,3) }
# end
# class ParserB < Parslet::Parser
# root :expression
# rule(:expression) { str('b') >> ParserA.new >> str('b') }
# end
#
# In the above example, ParserB would parse something like 'baaab'.
#
class Parslet::Parser < Parslet::Atoms::Base
include Parslet
class <<self # class methods
# Define the parsers #root function. This is the place where you start
# parsing; if you have a rule for 'file' that describes what should be
# in a file, this would be your root declaration:
#
# class Parser
# root :file
# rule(:file) { ... }
# end
#
# #root declares a 'parse' function that works just like the parse
# function that you can call on a simple parslet, taking a string as input
# and producing parse output.
#
# In a way, #root is a shorthand for:
#
# def parse(str)
# your_parser_root.parse(str)
# end
#
def root(name)
define_method(:root) do
self.send(name)
end
end
end
def try(source, context, consume_all)
root.try(source, context, consume_all)
end
def to_s_inner(prec)
root.to_s(prec)
end
end
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