File Coverage

lib/Table/BoxFormat/Unicode/CharClasses.pm

Criterion	Covered	Total	%
statement	32	32	100.0
branch			n/a
condition			n/a
subroutine	10	10	100.0
pod	3	3	100.0
total	45	45	100.0

package Table::BoxFormat::Unicode::CharClasses;
#                                [e-mail]
#                                22 Dec 2016


=head1 NAME

Table::BoxFormat::Unicode::CharClasses - character classes to work with db SELECT result formats

=head1 SYNOPSIS

   use Table::BoxFormat::Unicode::CharClasses ':all';

   $horizontal_dashes_plus_crosses_or_whitespace =
           qr{ ^
                [ \p{IsHor} \s ] +
               $  }x;

   $cross_character =
            qr{
                 \p{IsCross}
                    {1,1}   # just one
               }xms;

   $column_separator =
         qr{
            \s+         # require leading whitespace
            \p{IsDelim}
                {1,1}   # just one
            \s+         # require trailing whitespace
        }xms;


=head1 DESCRIPTION

Table::BoxFormat::Unicode::CharClasses, contains a number of
pre-defined character classes to assist in writing regular
expressions to match elements of typical database SELECT result
formats (see: L).

=head2 EXPORT

None by default, ':all' for all.

=cut

use 5.10.0;
use strict;
use warnings;
use utf8;
my $DEBUG = 1;
use Carp;
use Data::Dumper;

our (@ISA, @EXPORT_OK, %EXPORT_TAGS, @EXPORT);
BEGIN {
 require Exporter;
 @ISA = qw(Exporter);
 %EXPORT_TAGS = ( 'all' => [
 qw(
     IsHor
     IsCross
     IsDelim
    ) ] );
  @EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } );
  @EXPORT = qw(  ); # items to export into callers namespace by default (avoid this!)
}

our $VERSION = '0.01';


=head2 regexp properties

Definitons of some custom regexp character properties that might
be useful for projects such as L, that work with
the tabular text formats used by database monitors to display
select results.

=over

=cut

=item IsHor

Matches characters found in a "horizontal rule" row.

=cut

# defining character properties for regexp defaults
sub IsHor {
  my @codepoints =
    ('002D',  # -  \N{HYPHEN-MINUS}
     '002B',  # +  \N{PLUS SIGN}
     '2500',  # ─  \N{BOX DRAWINGS LIGHT HORIZONTAL}
     '253C',  # ┼  \N{BOX DRAWINGS LIGHT VERTICAL AND HORIZONTAL}
     );
  my $list = join "\n", @codepoints;
  return $list;
}

=item IsCross

Matches the "cross" characters used at line intersections.

=cut

sub IsCross {
  my @codepoints =
    (
     '002B',  # +  \N{PLUS SIGN}
     '253C',  # ┼  \N{BOX DRAWINGS LIGHT VERTICAL AND HORIZONTAL}
     );
  my $list = join "\n", @codepoints;
  return $list;
}

=item IsDelim

Matches the delimeter/separator characters used on column boundaries.

=cut

sub IsDelim {
  my @codepoints =
    (
     '007C',  #  |  \N{VERTICAL LINE}
     '2502',  #  │  \N{BOX DRAWINGS LIGHT VERTICAL}
    );
  my $list = join "\n", @codepoints;
  return $list;
}



1;

=head1 NOTES

=head2 about characters used in the above classes

=head3 unicode characters

the unicode psql format uses these three characters:

uniprops U+2502
U+2502 ‹│› \N{BOX DRAWINGS LIGHT VERTICAL}
    \pS \p{So}
    All Any Assigned InBoxDrawing Box_Drawing Common Zyyy So S Gr_Base
       Grapheme_Base Graph GrBase Other_Symbol Pat_Syn Pattern_Syntax PatSyn
       Print Symbol Unicode X_POSIX_Graph X_POSIX_Print

uniprops U+2500
U+2500 ‹─› \N{BOX DRAWINGS LIGHT HORIZONTAL}
    \pS \p{So}
    All Any Assigned InBoxDrawing Box_Drawing Common Zyyy So S Gr_Base
       Grapheme_Base Graph GrBase Other_Symbol Pat_Syn Pattern_Syntax PatSyn
       Print Symbol Unicode X_POSIX_Graph X_POSIX_Print

uniprops U+253c
U+253C ‹┼› \N{BOX DRAWINGS LIGHT VERTICAL AND HORIZONTAL}
    \pS \p{So}
    All Any Assigned InBoxDrawing Box_Drawing Common Zyyy So S Gr_Base
       Grapheme_Base Graph GrBase Other_Symbol Pat_Syn Pattern_Syntax PatSyn
       Print Symbol Unicode X_POSIX_Graph X_POSIX_Print


=head3 delimiter characters

Either of these two characters may be data delimiters,
the ascii vertical bar or the unicode "BOX DRAWINGS LIGHT VERTICAL":

    |│


=head1 SEE ALSO

L
L

=head1 AUTHOR

Joseph Brenner, [e-mail]

=head1 COPYRIGHT AND LICENSE

Copyright (C) 2016 by Joseph Brenner

This program is free software; you can redistribute it and/or modify it
under the terms of either: the GNU General Public License as published
by the Free Software Foundation; or the Artistic License.

See http://dev.perl.org/licenses/ for more information.

=cut