Class: Rley::SPPF::SPPFNode

Inherits:

Object

• Object
• Rley::SPPF::SPPFNode

Defined in:

lib/rley/sppf/sppf_node.rb

Overview

Abstract class. The generalization for all kinds of nodes occurring in a shared packed parse forest (SPPF).

Direct Known Subclasses

CompositeNode, LeafNode

Instance Attribute Summary

• #range ⇒ Lexical::TokenRange readonly

  A range of token indices corresponding to this node.

Instance Method Summary

• #initialize(aRange) ⇒ SPPFNode constructor

  Constructor.

• #origin ⇒ Integer

  Return the origin, that is, the index of the first token matched by this node.

Constructor Details

#initialize(aRange) ⇒ SPPFNode

Constructor

Parameters:

• aRange (Lexical::TokenRange)

# File 'lib/rley/sppf/sppf_node.rb', line 16

def initialize(aRange)
  @range = Lexical::TokenRange.new(aRange)
end

Instance Attribute Details

#range ⇒ Lexical::TokenRange (readonly)

A range of token indices corresponding to this node.

Returns:

• (Lexical::TokenRange)

# File 'lib/rley/sppf/sppf_node.rb', line 12

def range
  @range
end

Instance Method Details

#origin ⇒ Integer

Return the origin, that is, the index of the first token matched by this node.

Returns:

• (Integer)

# File 'lib/rley/sppf/sppf_node.rb', line 23

def origin
  range.low
end