in reply to Re^3: Closure warning with Perl 5.14?
in thread Closure warning with Perl 5.14?

This complains about uninitialized value (of course), but gives no warning in 5.14.0: 

use warnings;
use strict;

use constant duh => 0;
my $y = "X"   if duh;
sub x{ 
    print $y ? 'Okay' : 'bad';
}

x();
print "$y\n";

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And no warning even for this:

use warnings;
use strict;

my $y = "X"   if 0;
sub x{ 
    print $y ? 'Okay' : 'bad';
}

x();
print "$y\n";

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Re^5: Closure warning with Perl 5.14?
by JavaFan (Canon) on May 19, 2011 at 09:45 UTC
    Yeah, it only warns on my $var if 0, not on my $var = EXPR if COND. I do not know why.
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      To allow stuff like the following? 

      print(my $x = 1234) if COND;

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      Which is to say, they probably didn't want to step on anything that has remote chance of being legit.

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        But my $x if COND; doesn't warn either, unless COND is false. Not sure what print(my $x = 1234) if 0; would be good for. Note also that print(my $x = 1234) if COND; does not have a my $x = EXPR if COND subexpression, not even on a textual level.
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      That was a hack for getting state variables. So it might be found in code that should use state instead, and won't work as expected in the new versions.
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[d/l]
        Yeah, but what is the intention of all other code that uses: 
        my $var if COND;

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        ? Either the if COND is redundant, because it's always true, or it maybe false and you have the same issue. Also, 
        my $var = 0 if 0;

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        creates a "state" variable, yet there's no warning.

        Now, I'm usually not a fan of adding a warning for every little thing, but if there's a warning, it shouldn't be inconsistent on when it warns and when it doesn't.

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