Path: | lib/more/facets/dictionary.rb |
Last Update: | Tue Sep 22 08:13:43 +0000 2009 |
The Dictionary class is a Hash that preserves order. So it has some array-like extensions also. By defualt a Dictionary object preserves insertion order, but any order can be specified including alphabetical key order.
Just require this file and use Dictionary instead of Hash.
# You can do simply hsh = Dictionary.new hsh['z'] = 1 hsh['a'] = 2 hsh['c'] = 3 p hsh.keys #=> ['z','a','c'] # or using Dictionary[] method hsh = Dictionary['z', 1, 'a', 2, 'c', 3] p hsh.keys #=> ['z','a','c'] # but this don't preserve order hsh = Dictionary['z'=>1, 'a'=>2, 'c'=>3] p hsh.keys #=> ['a','c','z'] # Dictionary has useful extensions: push, pop and unshift p hsh.push('to_end', 15) #=> true, key added p hsh.push('to_end', 30) #=> false, already - nothing happen p hsh.unshift('to_begin', 50) #=> true, key added p hsh.unshift('to_begin', 60) #=> false, already - nothing happen p hsh.keys #=> ["to_begin", "a", "c", "z", "to_end"] p hsh.pop #=> ["to_end", 15], if nothing remains, return nil p hsh.keys #=> ["to_begin", "a", "c", "z"] p hsh.shift #=> ["to_begin", 30], if nothing remains, return nil
Originally ported from OrderHash 2.0, Copyright (c) 2005 jan molic
** Fixed initialize so the constructor blocks correctly effected dictionary rather then just the internal hash.
Copyright (c) 2005 Jan Molic, Thomas Sawyer
Ruby License
This module is free software. You may use, modify, and/or redistribute this software under the same terms as Ruby.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.