When UNIVERSAL::can is applied on a method that has been undefined, it produces a result that looks wrong to me. For example: 
#!/usr/bin/perl
use strict;
use warnings;

BEGIN { print "can=", __PACKAGE__->can('fred'), ";\n"; }
sub fred { print "fred\n"; }
print "can=", __PACKAGE__->can('fred'), ";\n";
fred;
undef &fred;
print "can=", __PACKAGE__->can('fred'), ";\n";
fred;

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produces: 
Use of uninitialized value in print at test.pl line 5.
can=;
can=CODE(0x81199b4);
fred
can=CODE(0x81199b4);
Undefined subroutine &main::fred called at test.pl line 11.

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That's all as I expect except the last call of can returns a code address that no longer works, and leads to a run-time error if used. I would have expected can to return undef on that occasion.
Am I looking at this the wrong way, or is can dented?

In reply to can undefined methods? by Dave Howorth

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