Re: Converting array of hash references to hash

You can also answer your question w/o creating a hash:

$ams_ip = "" unless grep { $ams_ip eq $_->{'deviceIp'} } @{$ams_hosts}
+;
[download]

but this would be computationally more expensive if you need to perform this query many times.

Comment on Re: Converting array of hash references to hash Download Code

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Re^2: Converting array of hash references to hash by anirudh.agarwal (Novice) on Apr 22, 2013 at 13:33 UTC
This one definitely works. Thanks. This query is executed only once per request in my case. I hope in that case even if `@{$ams_hosts}` has a large data, it wont be expensive. :) Thanks again	[reply] [d/l]
Re^2: Converting array of hash references to hash by anirudh.agarwal (Novice) on May 01, 2013 at 12:54 UTC
I verified that use of `any` instead of `grep` increases the performance.	[reply] [d/l] [select]
Re^3: Converting array of hash references to hash by LanX (Saint) on May 01, 2013 at 13:12 UTC
> I verified that use of `any` instead of `grep` increases the performance. sure, but List::MoreUtils is not core... `lanx@nc10-ubuntu:~$ corelist List::MoreUtils List::MoreUtils was not in CORE (or so I think)` [download] ... thats why it's easier to show working code w/o dependencies. With List::MoreUtils present `any` is for sure the better choice! Cheers Rolf ( addicted to the Perl Programming Language)	[reply] [d/l] [select]
Re^2: Converting array of hash references to hash by anirudh.agarwal (Novice) on May 01, 2013 at 09:27 UTC
When I check the above statement using Perl Critic, it finds the following violation. `"grep" used in boolean context`. I see this strange.	[reply] [d/l]
Re^3: Converting array of hash references to hash by anirudh.agarwal (Novice) on May 01, 2013 at 09:36 UTC
I then found that grep would search for the rest of the array even if a match is found in the first record itself. I believe `any` should be used. Let me try the following `$ams_ip = "" unless any { $ams_ip eq $_->{'deviceIp'} } @{$ams_hosts};` Please let me know if I am wrong. Thanks :)	[reply] [d/l] [select]