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 $

[download]

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;$@ = '';

[download]

How do I determine if a variable contains a type glob?

In reply to How do I determine if a variable contains a type glob? by dpchrist

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