Method: Sequitur::Production#derive_step

Defined in:
lib/sequitur/production.rb

#derive_step(another) ⇒ Object

Replace every occurrence of 'another' production in self.rhs by the symbols in the rhs of 'another'.

Given the production p_A : a p_B b p_B c

And the production p_B : x y

Then...

p_A.derive_step(p_B)

Modifies p_A as into: p_A -> a x y b x y c

Examples:

Synopsis

Parameters:



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# File 'lib/sequitur/production.rb', line 204

def derive_step(another)
  (0...rhs.size).to_a.reverse_each do |index|
    next unless rhs[index] == another

    rhs.insert_at(index + 1, another.rhs)
    another.decr_refcount
    rhs.delete_at(index)
  end

  recalc_digrams
end