Copyright © 2001,2003 Akinori MUSHA <knu@iDaemons.org>
All rights reserved. You can redistribute and/or modify it under the same terms as Ruby.
$Idaemons: /home/cvs/rb/abbrev.rb,v 1.2 2001/05/30 09:37:45 knu Exp $ $RoughId: abbrev.rb,v 1.4 2003/10/14 19:45:42 knu Exp $ $Id: abbrev.rb 25189 2009-10-02 12:04:37Z akr $ Calculate the set of unique abbreviations for a given set of strings.
require 'abbrev' require 'pp' pp Abbrev::abbrev(['ruby', 'rules']).sort
Generates:
[["rub", "ruby"], ["ruby", "ruby"], ["rul", "rules"], ["rule", "rules"], ["rules", "rules"]]
Also adds an abbrev method to class Array.
Given a set of strings, calculate the set of unambiguous abbreviations for those strings, and return a hash where the keys are all the possible abbreviations and the values are the full strings. Thus, given input of “car” and “cone”, the keys pointing to “car” would be “ca” and “car”, while those pointing to “cone” would be “co”, “con”, and “cone”.
The optional pattern parameter is a pattern or a string. Only those input strings matching the pattern, or begging the string, are considered for inclusion in the output hash
# File abbrev.rb, line 44
def abbrev(words, pattern = nil)
table = {}
seen = Hash.new(0)
if pattern.is_a?(String)
pattern = /^#{Regexp.quote(pattern)}/ # regard as a prefix
end
words.each do |word|
next if (abbrev = word).empty?
while (len = abbrev.rindex(/[\w\W]\z/)) > 0
abbrev = word[0,len]
next if pattern && pattern !~ abbrev
case seen[abbrev] += 1
when 1
table[abbrev] = word
when 2
table.delete(abbrev)
else
break
end
end
end
words.each do |word|
next if pattern && pattern !~ word
table[word] = word
end
table
end