I would like to write a subroutine is_typeglob($) that returns true when passed a type glob and returns false when not passed a type glob. (I already have a subroutine is_typeglob_ref($).)
This is a scratch program I wrote to experiment with some ideas:
2016-12-04 12:35:05 dpchrist@debian ~/sandbox/perl
$ cat is_typeglob.pl
#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;
$Data::Dumper::Indent = 0;
use Scalar::Util qw(blessed openhandle reftype);
{
no warnings 'once';
open (FH, '<', $0) or die "ERROR: open(): $!";
}
for (
q(*ARGV ),
q(*ARGV cmp '*ARGV' ),
q(*ARGV cmp "*ARGV" ),
q(*ARGV cmp '*::ARGV' ),
q(*ARGV cmp "*::ARGV" ),
q(ref *ARGV ),
q(blessed *ARGV ),
q(openhandle *ARGV ),
q(reftype *ARGV ),
) {
my $code = $_;
my $r = eval $code;
print Data::Dumper->Dump([$code, $r, $@], [qw(code r @)]), "\n";
}
# $Id: is_typeglob.pl,v 1.1 2016/12/04 20:35:04 dpchrist Exp $
Here is a sample run:
2016-12-04 12:42:14 dpchrist@debian ~/sandbox/perl
$ perl is_typeglob.pl
$code = '*ARGV ';$r = *::ARGV;$@ = '';
$code = '*ARGV cmp \'*ARGV\' ';$r = 1;$@ = '';
$code = '*ARGV cmp "*ARGV" ';$r = 1;$@ = '';
$code = '*ARGV cmp \'*::ARGV\' ';$r = 1;$@ = '';
$code = '*ARGV cmp "*::ARGV" ';$r = 1;$@ = '';
$code = 'ref *ARGV ';$r = '';$@ = '';
$code = 'blessed *ARGV ';$r = undef;$@ = '';
$code = 'openhandle *ARGV ';$r = undef;$@ = '';
$code = 'reftype *ARGV ';$r = undef;$@ = '';
How do I determine if a variable contains a type glob?