RegexpTrie

Synopsis

#!/usr/bin/env ruby
require 'regexp_trie'

# like Regexp.union()
p RegexpTrie.union(%w(foobar fooxar foozap fooza)) # /foo(?:bar|xar|zap?)/
p RegexpTrie.union(%w(foobar fooxar foozap fooza), option: Regexp::IGNORECASE) # /foo(?:bar|xar|zap?)/i

# or object-oriented interface
rt = RegexpTrie.new
%w(foobar fooxar foozap fooza).each do |word|
  rt.add(word)
end
p rt.to_regexp # /foo(?:bar|xar|zap?)/

See also the original Regexp::Trie in Perl.

Description

RegexpTrie takes an arbitrary number of regular expressions and assembles them into a single regular expression (or RE) that matches all that the individual REs match.

In other words, this library provides a limited but optimized version of Regexp.union(), even thouh there are some incompatibilities with it.

Installation

Add this line to your application's Gemfile:

gem 'regexp_trie'

Incompatibilities with the built-in Regexp.union()

• RegexpTrie handles only literals. i.e. RegexpTrie.union("foo.*bar") produces /foo\.\*bar/, not /foo.*bar/
• RegexpTrie cannot handle empty strings.
• The order of words does not matter:
  • Regexp.union("foo", "foobar").match("foobar") # => #<MatchData "foo">
  • RegexpTrie.union("foo", "foobar").match("foobar") # => #<MatchData "foobar">

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/gfx/regexp_trie.

See Also

• https://metacpan.org/pod/Regexp::Assemble
• https://metacpan.org/pod/Regexp::Trie

License

The gem is available as open source under the terms of the MIT License.

The original code is @dankogai's Regexp::Trie.