Re: Hashing uninitialized values when no value returned from DBI sql select

In Perl 5.10, you can say,

$myhash{$val_1} = $val_2 // '';
[download]

Otherwise, I might say,

$myhash{$val_1} = defined $val_2 ? $val_2 : '';
[download]

Update: And you can always turn off warnings.

foreach $val_1 (keys %myhash) {
   no warnings 'uninitialized';
   print "myhash{$val_1} = $myhash{$val_1}\n";
}
[download]

You can selectively and lexically turn off/on warnings as you like. Generally it's a good idea to limit the lack of warnings to the smallest scope possible. See perllexwarn for a list of the warnings categories you can toggle.

Comment on Re: Hashing uninitialized values when no value returned from DBI sql select Select or Download Code

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Re^2: Hashing uninitialized values when no value returned from DBI sql select by punch_card_don (Curate) on Feb 27, 2008 at 20:51 UTC
I thought I had 5.1, but I must not, because `$myhash{$val_1} = $val_2 // '';` [download] produces `Illegal division by zero` [download] on my system.	[reply] [d/l] [select]
Re^3: Hashing uninitialized values when no value returned from DBI sql select by FunkyMonk (Bishop) on Feb 27, 2008 at 23:48 UTC
I thought I had 5.1, but I must not, because 5.10? Well, what does `perl -v` say?	[reply] [d/l] [select]
Re^4: Hashing uninitialized values when no value returned from DBI sql select by punch_card_don (Curate) on Feb 28, 2008 at 03:49 UTC
Yep - 5.8.8	[reply]
Re^3: Hashing uninitialized values when no value returned from DBI sql select by kyle (Abbot) on Feb 27, 2008 at 21:01 UTC
With Perl 5.8.8: `$ perl -e '$v2=undef;$v1 = $v2 // "";' Search pattern not terminated at -e line 1. $ perl -e '$v2=undef;$v1 = $v2 / "";' Illegal division by zero at -e line 1.` [download]	[reply] [d/l]