Class: Yaparc::Alt

Inherits:

Object

• Object
• Yaparc::Alt

Includes:

Parsable

Defined in:

lib/yaparc.rb

Overview

class AltParser

Constant Summary

Constants included from Parsable

Parsable::IS_ALPHANUM, Parsable::IS_DIGIT, Parsable::IS_LOWER, Parsable::IS_SPACE, Parsable::IS_WHITESPACE

Instance Attribute Summary

Attributes included from Parsable

#tree

Instance Method Summary

• #initialize(*parsers) ⇒ Alt constructor

  A new instance of Alt.

Methods included from Parsable

#eval, included, #parse

Constructor Details

#initialize(*parsers) ⇒ Alt

Returns a new instance of Alt.

# File 'lib/yaparc.rb', line 224

def initialize(*parsers)
  @parser = lambda do |input|
    initial_result = Result::OK.new(:input => input)
    final_result = Result::Fail.new(:input => input)
    parsers.each do |parser|
#          case result = parser.parse(initial_result.input)
      case result = parser.parse(input)
      when Result::Fail
        next
      when Result::Error
        return Result::Error.new(:value => result.value, :input => result.input)
      when Result::OK
        break final_result = result
      else
        raise
      end
    end
    final_result
  end
end