Re^4: Check for variable without leaving a trace

It mostly can (or at least could before 5.11), using defined:

main @> $test = 1
1
main @> defined $test
1
main @> defined %test
''
main @> %test2 = 1,2
1 2
main @> defined $test2
''
main @> defined %test2
1
main @> %test3 = ()
undef
main @> defined %test3
''
main @> defined $test3
''
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It doesn't detect an empty hash, but that's good enough for me.

Comment on Re^4: Check for variable without leaving a trace Download Code

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Re^5: Check for variable without leaving a trace by Fox (Pilgrim) on Dec 09, 2009 at 17:07 UTC
no, I meant, perl can tell if $a or %a is defined but given 'a' it can't say which one was used.	[reply]