Sha256: b484c409bf7d07e6cb5458671c0e73967ef0f0e5d602c8564b49dbb9a7c95b3b

Contents?: true

Size: 1.96 KB

Versions: 3

Compression:

Stored size: 1.96 KB

Contents

module Regexp::Expression
  class Subexpression < Regexp::Expression::Base

    # Traverses the subexpression (depth-first, pre-order) and calls the given
    # block for each expression with three arguments; the traversal event,
    # the expression, and the index of the expression within its parent.
    #
    # The event argument is passed as follows:
    #
    # - For subexpressions, :enter upon entering the subexpression, and
    #   :exit upon exiting it.
    #
    # - For terminal expressions, :visit is called once.
    #
    # Returns self.
    def traverse(include_self = false, &block)
      return enum_for(__method__, include_self) unless block_given?

      block.call(:enter, self, 0) if include_self

      each_with_index do |exp, index|
        if exp.terminal?
          block.call(:visit, exp, index)
        else
          block.call(:enter, exp, index)
          exp.traverse(&block)
          block.call(:exit, exp, index)
        end
      end

      block.call(:exit, self, 0) if include_self

      self
    end
    alias :walk :traverse

    # Iterates over the expressions of this expression as an array, passing
    # the expression and its index within its parent to the given block.
    def each_expression(include_self = false, &block)
      return enum_for(__method__, include_self) unless block_given?

      block.call(self, 0) if include_self

      each_with_index do |exp, index|
        block.call(exp, index)
        exp.each_expression(&block) unless exp.terminal?
      end
    end

    # Returns a new array with the results of calling the given block once
    # for every expression. If a block is not given, returns an array with
    # each expression and its level index as an array.
    def flat_map(include_self = false)
      result = []

      each_expression(include_self) do |exp, index|
        if block_given?
          result << yield(exp, index)
        else
          result << [exp, index]
        end
      end

      result
    end
  end
end

Version data entries

3 entries across 3 versions & 3 rubygems

Version Path
call_your_name-0.1.0 vendor/bundle/ruby/3.1.0/gems/regexp_parser-2.7.0/lib/regexp_parser/expression/methods/traverse.rb
zilla-0.2.0 vendor/bundle/ruby/3.2.0/gems/regexp_parser-2.7.0/lib/regexp_parser/expression/methods/traverse.rb
regexp_parser-2.7.0 lib/regexp_parser/expression/methods/traverse.rb