File-MultilineGrep

To be considered text files having repeated structures. These structures possess repeated
start delimiter, optional stop delimiter and variable contents. That is some or all fields
of these structures are optional.
A task is to select all whole structures, that contain a specified pattern.
This can be done using a multiline regular expressions. But there is a performance issue:
Processing time using regular expression is not directly proportional to amount of structures,
so that increasing of this amount might cause the reqular expression will never finish.
Processing time of the proposed function is directly proportional to amount of structures.

   file_multiline_grep( $begin_pattern      #                     regular expression
                      , $finish_pattern     # optional parameter, regular expression
                      , $middle_pattern     #                     regular expression
                      , $numeration         # if false - not enumerate output lines
                      , $input_file         # optional parameter
                                            # if false - read from STDIN
                      , $output_separator); # optional parameter


EXAMPLE

   use File::MultilineGrep;

   file_multiline_grep ('person_id'
                      , 'end_person'
                      , 'Giant'
                      , 'enumerate_lines'
                      , 'most_famous_people'
                      , '------

reads all records from a file 'most_famous_people' 
(where line enumeration doesn't belong to the file):

  1 person_id  - 001
  2 profession - Prophet
  3 first name - Moses
  4 birthyear  - 1391 BCE
  5 end_person    
  6    ...
  7 person_id  - 002
  8 profession - Giant
  9 first name - Samson
 10 birthyear  - Unknown
 11 end_person   
 12    ...
 13 person_id  - 003
 14 profession - King
 15 first name - David
 16 birthyear  - 1040 BCE
 17 end_person   
 18    ...
 19 person_id  - 004
 20 profession - Giant
 21 first name - Goliath
 22 birthyear  - 135  BCE
 23 end_person   

that begin with 'person_id', finish with 'end_person' and contain a pattern 'Giant':

   7: person_id  - 002 
   8= profession - Giant
   9: first name - Samson
  10: birthyear  - Unknown
  11: end_person
 ------
  19: person_id  - 004 
  20= profession - Giant
  21: first name - Goliath
  22: birthyear  - 135  BCE 
  23: end_person
 ------

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 File::MultilineGrep

You can also look for information at:

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

    AnnoCPAN, Annotated CPAN documentation
        http://annocpan.org/dist/File-MultilineGrep

    CPAN Ratings
        http://cpanratings.perl.org/d/File-MultilineGrep

    Search CPAN
        http://search.cpan.org/dist/File-MultilineGrep/


LICENSE AND COPYRIGHT

Copyright (C) 2013 Mart E. Rivilis

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:

L<http://www.perlfoundation.org/artistic_license_2_0>

Any use, modification, and distribution of the Standard or Modified
Versions is governed by this Artistic License. By using, modifying or
distributing the Package, you accept this license. Do not use, modify,
or distribute the Package, if you do not accept this license.

If your Modified Version has been derived from a Modified Version made
by someone other than you, you are nevertheless required to ensure that
your Modified Version complies with the requirements of this license.

This license does not grant you the right to use any trademark, service
mark, tradename, or logo of the Copyright Holder.

This license includes the non-exclusive, worldwide, free-of-charge
patent license to make, have made, use, offer to sell, sell, import and
otherwise transfer the Package with respect to any patent claims
licensable by the Copyright Holder that are necessarily infringed by the
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