Just use undef e.g 
sub foo {
  print "yep\n";
}

@foo = $foo = 'a string';
my $f = 'foo';

foo() if defined &foo;

undef &$f;

print "nope\n" unless defined &foo;

print "\$foo: $foo\n";
print "\@foo: @foo\n";

__output__

yep
nope
$foo: a string
@foo: a string

[download]
HTH

_________
broquaint

In reply to Re: undefining one slot of a typeglob by broquaint
in thread undefining one slot of a typeglob by AidanLee

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