Module: Antelope::Generator::Base::Extra

Included in:
Antelope::Generator::Base
Defined in:
lib/antelope/generator/base/extra.rb

Overview

Includes some extra processed information about the grammar to be provided to general generators.

Instance Method Summary collapse

Instance Method Details

#productions ⇒ Array<Array<(Ace::Token::Nonterminal, Numeric, String)>]

Returns an array of the production information of each production needed by the parser. The first element of any element in the array is an Ace::Token::Nonterminal that that specific production reduces to; the second element is a number describing the number of items in the right hand side of the production; the string represents the action that should be taken on reduction.

This information is used for :reduce actions in the parser; the value of the :reduce action corresponds to the array index of the production in this array.

Returns:

  • (Array<Array<(Ace::Token::Nonterminal, Numeric, String)>]) —

    Array]



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# File 'lib/antelope/generator/base/extra.rb', line 40

def productions
  grammar.all_productions.map do |production|
    [production[:label],
     production[:items].size,
     production[:block]]
  end
end

#table ⇒ Array<Hash<Symbol => Array<(Symbol, Numeric)>>>

The actual table that is used for parsing. This returns an array of hashes; the array index corresponds to the state number, and the hash keys correspond to the lookahead tokens. The hash values are an array; the first element of that array is the action to be taken, and the second element of the array is the argument for that action. Possible actions include :accept, :reduce, and :state; :accept means to accept the string; :reduce means to perform the given reduction; and :state means to transition to the given state.

Returns:

  • (Array<Hash<Symbol => Array<(Symbol, Numeric)>>>) 


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# File 'lib/antelope/generator/base/extra.rb', line 19

def table
  if mods[:tableizer].is_a? Generation::Tableizer
    mods[:tableizer].table
  else
    []
  end
end