Re: 'my' with 'if 0' retains old value

Quote diotalevi:

my() has a runtime effect. You *always* (unless you're doing something freakish) want that to happen. The my $var STATEMENT-MODIFIER allows the runtime part of my() to potentially not happen.

In other words,
my $var = ... if/unless/while/for/foreach ...
is wrong and/or buggy. Use
my $var;
$var = ... if/unless/while/for/foreach ...
instead

In this case, replace
my $v2 = -2 if 0;
with
my $v2;
$v2 = -2 if 0;

PS - You post here regularly. You should start heeding "Clean Your Room" in How (Not) To Ask A Question and start indenting your code.

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Re^2: 'my' with 'if 0' retains old value by diotalevi (Canon) on Apr 21, 2006 at 05:37 UTC
You can use Perl::Critic to automatically find such fugly code as well. Neat, eh? ⠤⠤ ⠙⠊⠕⠞⠁⠇⠑⠧⠊	[reply]
Re^2: 'my' with 'if 0' retains old value by bart (Canon) on Apr 21, 2006 at 15:23 UTC
`my $v2; $v2 = -2 if 0;` [download] Surely that won't do anything useful. I mean, it'll do the same as `my $v2;` [download] Hence: no static variable, no value assigned. Anyway: `my $v2 if 0;` [download] will create a static variable. But IMO that's a coincidence of the implementation, I wouldn't count on it.	[reply] [d/l] [select]
Re^3: 'my' with 'if 0' retains old value by ikegami (Patriarch) on Apr 21, 2006 at 15:24 UTC
What if `0` is actually `DEBUG`? I don't presume to know what the real code is like.	[reply] [d/l] [select]
Re^4: 'my' with 'if 0' retains old value by diotalevi (Canon) on Apr 21, 2006 at 18:25 UTC
or what if `0` is actually `rand() > .5`? Then it's a static variable some of the time. ⠤⠤ ⠙⠊⠕⠞⠁⠇⠑⠧⠊	[reply] [d/l] [select]