Contents

# -*- coding: utf-8 -*-
module TreeVisitor
  #
  # Executes a block when enter in a node
  # The block are defined from on_enter_X methods
  # The blocks take as argument only the node
  #
  class CallbackTreeNodeVisitor < BasicTreeNodeVisitor

    def initialize
      @root = nil
      @stack = []
      @action_enter_tree_node = nil
      @action_visit_leaf_node = nil
    end

    def on_enter_tree_node( &action )
      @action_enter_tree_node = action
    end

    def on_visit_leaf_node( &action )
      @action_visit_leaf_node = action
    end

    def enter_tree_node( tree_node )
      # parent_node = @stack.empty? ? nil : @stack.last
      @root = tree_node if @stack.empty?
      @stack.push( tree_node )
      @action_enter_tree_node.call( tree_node ) if @action_enter_tree_node
    end

    def exit_tree_node( tree_node )
      @stack.pop
    end

    def visit_leaf_node( leaf_node )
      # parent_node = @stack.last
      @action_visit_leaf_node.call( leaf_node ) if @action_visit_leaf_node
    end

  end
end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
treevisitor-0.1.6	lib/treevisitor/visitors/callback_tree_node_visitor.rb