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### Re: Easy hash question (uninitialized value)

by Lotus1 (Priest)
 on May 16, 2018 at 13:54 UTC ( #1214657=note: print w/replies, xml ) Need Help??

in reply to Easy hash question (uninitialized value)

Also check out the function exists. It lets you test if a key is in a hash. In this case it would help you debug but it's useful in general for validating hash keys, especially when they come from user input.

if( exists $j{$number} ) {
say $j{$number};
say "done";
}
else {
say "<\$number> is not a key in \%j"
}

[download]

Here is the result of running it:

C:\usr\pm\hash>perl 1214633.pl
4
4

<4
> is not a key in %j
[download]

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