# Grep::Query 1.004

This module implements a limited query language for logical expressions
(AND, OR, NOT, parenthesized, ...etc) and apply it to lists of data for
selecting a subset, similar to using "grep" with a block/regexp in the code.

A reason for not using grep with a regular code block directly is that the
original impetus for its existence was to allow a user running a command-line
tool to submit an arbitrary query for a list the tool had somehow generated
(e.g. a list of file names).

The initial approach of having the user pass individual regexes for doing
"include/exclude" operations proved to be too limiting if the selection
criteria became more complex. Hence the notion of a query language that
makes it possible to express more complex combinations of regexes was born.  

Matching can be most readily done on plain lists of scalar strings/values,
but by providing a 'field accessor', matching can be done against lists of
arbitrary objects/hashes using all possible data they contain, including
doing both string (regexes, eq/ne/gt/ge/lt/le) as well as numerical
(==/!=/>/>=/</<=) comparisons.

Arguably, it may be seen as a 'grep' on steroids :-).

### INSTALLATION

To install this module, run the following commands:

	perl Makefile.PL
	make
	make test
	make install

### SUPPORT AND DOCUMENTATION

After installing, you can find documentation for this module with the
perldoc command.

    perldoc Grep::Query

You can also look for information at:

    RT, CPAN's request tracker (report bugs here)
        http://rt.cpan.org/NoAuth/Bugs.html?Dist=Grep-Query

    AnnoCPAN, Annotated CPAN documentation
        http://annocpan.org/dist/Grep-Query

    CPAN Ratings
        http://cpanratings.perl.org/d/Grep-Query

    Search CPAN
        http://metacpan.org/dist/Grep-Query/

##### LICENSE AND COPYRIGHT

Copyright (C) 2016 Kenneth Olwing

This program is free software; you can redistribute it and/or modify it
under the terms of the the Artistic License (2.0). You may obtain a
copy of the full license at:

http://www.perlfoundation.org/artistic_license_2_0

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or distribute the Package, if you do not accept this license.

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