WordList

A Hash subclass designed for mapping word lists to token types.

License:	LGPL / ask the author
Version:	2.0 (2011-05-08)

A WordList is a Hash with some additional features. It is intended to be used for keyword recognition.

WordList is optimized to be used in Scanners, typically to decide whether a given ident is a special token.

For case insensitive words use WordList::CaseIgnoring.

Example:

 # define word arrays
 RESERVED_WORDS = %w[
   asm break case continue default do else
 ]

 PREDEFINED_TYPES = %w[
   int long short char void
 ]

 # make a WordList
 IDENT_KIND = WordList.new(:ident).
   add(RESERVED_WORDS, :reserved).
   add(PREDEFINED_TYPES, :predefined_type)

 ...

 def scan_tokens tokens, options
   ...

   elsif scan(/[A-Za-z_][A-Za-z_0-9]*/)
     # use it
     kind = IDENT_KIND[match]
     ...

Methods

Classes and Modules

Class CodeRay::WordList::CaseIgnoring

Public Class methods

new(default = false)

Create a new WordList with default as default value.

→ show source

# File lib/coderay/helpers/word_list.rb, line 48
    def initialize default = false
      super default
    end

Public Instance methods

add(words, value = true)

Add words to the list and associate them with value.

Returns self, so you can concat add calls.

→ show source

# File lib/coderay/helpers/word_list.rb, line 55
    def add words, value = true
      words.each { |word| self[word] = value }
      self
    end