Class: Zenlish::ZParser

Inherits:
Object
  • Object
show all
Defined in:
lib/zenlish/parser/zparser.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ ZParser

Returns a new instance of ZParser.



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# File 'lib/zenlish/parser/zparser.rb', line 11

def initialize
  # Create a Rley facade object
  @engine = Rley::Engine.new do |config|
    config.diagnose = true
  end

  # Step 1. Load Zenlish grammar
  @engine.use_grammar(ZenlishGrammar)
end

Instance Attribute Details

#engine ⇒ Object (readonly)

Returns the value of attribute engine.



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# File 'lib/zenlish/parser/zparser.rb', line 9

def engine
  @engine
end

Instance Method Details

#parse(tokenSeq) ⇒ Rley::PTree;;ParseTree Also known as: to_ptree

Parse the sequence of words into a parse tree.

Returns:

  • (Rley::PTree;;ParseTree) —

    the resulting parse tree.

Raises:

  • (StandardError) —

    Fails when the parse is ambiguous.



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# File 'lib/zenlish/parser/zparser.rb', line 24

def parse(tokenSeq)
  result = earley_parse(tokenSeq)

  # Convert into a parse tree
  engine.to_ptree(result)
end

#to_pforest(tokenSeq) ⇒ Rley::SPPF::ParseForest

Parse the sequence of words into a parse forest. Parse forests are needed when dealing with ambiguous input.

Returns:

  • (Rley::SPPF::ParseForest) —

    the resulting parse forest.



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# File 'lib/zenlish/parser/zparser.rb', line 36

def to_pforest(tokenSeq)
  result = earley_parse(tokenSeq)
  # puts result

  # Convert into a parse forest
  engine.to_pforest(result)
end