... and there's a bit of magic that I hadn't realized before, because you can do the same thing with a coderef.
use Config;
my $sub = *Config::non_bincompat_options{CODE};
print "defined before\n" if defined &$sub;
$sub->();
print "defined after\n" if defined &$sub;

[download]
Same result: not defined before, but defined after.

In reply to Re^3: does a subroutine exist? defined vs glob by Anonymous Monk
in thread does a subroutine exist? defined vs glob by bulk88

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