Re: accessing data in hash

Hi ccfc1986,

..I want to be able to loop through the data, and check the current JobID, when i find a match (say 33) i want to grab the State field and do a check against it..

You mean something like so:

print map { $_->{State} if $_->{ID} == 32 } @{ $hash->{data} };
[download]

 
for my $state ( @{ $hash->{data} } ) {
    print $state->{State} if $state->{ID} == 32;
}
[download]

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If you show me, I'll remember.
if you involve me, I'll understand.
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Comment on Re: accessing data in hash Select or Download Code

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Re^2: accessing data in hash by AnomalousMonk (Archbishop) on Mar 29, 2014 at 20:38 UTC
`print map { $_->{State} if $_->{ID} == 32 } @{ $hash->{data} };` ccfc1986: Be aware that the processing of this data flow is IMHO problematic. For every element processed that does not match the desired `ID`, an extraneous empty string is returned (the `''` pairs in the example below), the result of the ~~false evaluation~~ \| evaluation as false of the `if` conditional expression. I think NetWallah's use of grep is preferable. `c:\@Work\Perl\monks>perl -wMstrict -le "my $hash = { 'data' => [ { 'ID' => 32, 'State' => 'Stopped' }, { 'ID' => 33, 'State' => 'Stopped' }, { 'ID' => 31, 'State' => 'Running' }, ], }; ;; my @ra = map { $_->{State} if $_->{ID} == 32 } @{ $hash->{data} }; printf qq{'$_' } for @ra; " 'Stopped' '' ''` [download]	[reply] [d/l] [select]
Re^3: accessing data in hash by kcott (Archbishop) on Mar 29, 2014 at 21:43 UTC
You make a good point. Writing the `map` like this removes those empty strings from the result: `map { $_->{ID} == 32 ? $_->{State} : () }` [download] -- Ken	[reply] [d/l] [select]