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TextQuery

Does it match? When regular expressions are not enough, textquery is the answer. For example, regular expressions cannot evaluate recursive rules and often result in overly verbose and complicated expressions.

Textquery is a simple PEG grammar with support for:

  • AND (spaces are implicit AND's)
  • OR
  • NOT (- is an alias)
  • 'quoted strings'
  • fuzzy matching
  • case (in)sensitive
  • attribute tags (e.g. surname:Smith)
  • custom delimiters (default is whitespace for words, : for attributes)

TextQuery in the wild: PostRank, PaperTrail, and others!

Example

TextQuery.new("'to be' OR NOT 'to_be'").match?("to be")   # => true

TextQuery.new("-test").match?("some string of text")      # => true
TextQuery.new("NOT test").match?("some string of text")   # => true

TextQuery.new("a AND b").match?("b a")                    # => true
TextQuery.new("a AND b").match?("a c")                    # => false

q = TextQuery.new("a AND (b AND NOT (c OR d))")
q.match?("d a b")                                         # => false
q.match?("b")                                             # => false
q.match?("a b cdefg")                                     # => true

TextQuery.new("a~").match?("adf")                         # => true
TextQuery.new("~a").match?("dfa")                         # => true
TextQuery.new("~a~").match?("daf")                        # => true
TextQuery.new("2~a~1").match?("edaf")                     # => true
TextQuery.new("2~a~2").match?("edaf")                     # => false

TextQuery.new("a", :ignorecase => true).match?("A b cD")  # => true

License

The MIT License - Copyright (c) 2011 Ilya Grigorik