#!/usr/bin/perl

use strict;
use warnings;

use Getopt::Long qw(
	:config
	posix_default
	gnu_compat
	bundling
	no_auto_abbrev
	no_ignore_case
);

my $column=1;

@ARGV = grep  $_ !~ /\A--c\b/, @ARGV;

#if( grep s/\A--c\b=?.*//, @ARGV ){ $column = 100 };

# \b can be replaced with (?!o) for finer resolution
#if( grep s/\A--c(?!o)=?.*//, @ARGV ){ $column = 100 };


GetOptions(
	'column|c=i' => \$column,
) or die;

print "\$column is $column\n";

die if $column < 1;

__END__

# grep filtered
$ ~/Desktop/gol.pl --c 2 --c=2 --c= 2 --c = 2
$column is 1

# grep substitution conditional
$ ~/Desktop/gol.pl --c= 2 --c = 2 --c 2 --c=2 
$column is 100

##</code><code>##

#!/usr/bin/perl
# first attempt, non-working as the 
# long option is also discounted
use strict;
use warnings;

use Getopt::Long qw(
	:config
	posix_default
	gnu_compat
	bundling
	no_auto_abbrev
	no_ignore_case
);

my $column = 1;

#print map "[$_]", @ARGV, "\n";

#exclude the unwanted format with a filtering grep
@ARGV = grep $_ !~ /\A--c=/, @ARGV;

# remove the offending format using substition operator and test to see if you did
# if( grep s/\A--c=.*//, @ARGV ){ $column = 100 };

#print map "[$_]", @ARGV, "\n";

GetOptions(
	'column|c=i' => \$column,
) or die;

print "\$column is $column\n";

die if $column < 1;

__END__

$ ~/Desktop/gol.pl --column=2
$column is 2

$ ~/Desktop/gol.pl -c2
$column is 2

$ ~/Desktop/gol.pl --c=2
$column is 1

$ ~/Desktop/gol.pl -c=2
Value "=2" invalid for option c (number expected)
Unknown option: =
Unknown option: 2
Died at ~/Desktop/gol.pl line 19.

# using grep and substitution as conditional
$ ~/Desktop/gol.pl --c=2
$column is 100

#but also doesnt allow 
$ ~/Desktop/gol.pl --column 2
$column is 1