sub isIt{ local $^W;  ref( \$_[0] ) =~ m[GLOB] ? 1  : 0; }

##</code><code>##

[0]{} Perl> printf "%s: %d\n", $_, isIt( $_ ) for *ARGV, *INC, *SIG, *MATCH, *FH, *A, *B, *STDOUT, *CORE::say;; # *anything
*main::ARGV: 1
*main::INC: 1
*main::SIG: 1
*main::MATCH: 1
*main::FH: 1
*main::A: 1
*main::B: 1
*main::STDOUT: 1
*CORE::say: 1