Class: Panini::Grammar

Inherits:
Object
  • Object
show all
Defined in:
lib/grammar.rb

Overview

The Grammar stores the start symbol and nonterminals.

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Grammar

Returns a new instance of Grammar.



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# File 'lib/grammar.rb', line 7

def initialize
  @nonterminals = []
end

Instance Method Details

#add_nonterminal(name = nil) ⇒ Object

Add a nonterminal to the grammar.



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# File 'lib/grammar.rb', line 22

def add_nonterminal(name = nil)
  Panini::Nonterminal.new(name).tap do |new_nonterminal|
    @nonterminals << new_nonterminal
  end
end

#nonterminals ⇒ Object

The list of nonterminals in the grammar.



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# File 'lib/grammar.rb', line 29

def nonterminals
  @nonterminals.dup
end

#start ⇒ Object

Returns the grammar’s start symbol. This will be the first nonterminal added to the grammar if it hasn’t been specified.



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# File 'lib/grammar.rb', line 13

def start
  @start ||= @nonterminals[0]
end

#start=(start) ⇒ Object 



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# File 'lib/grammar.rb', line 17

def start=(start)
  @start = start
end