Re: Is item in array

Dr.Ruud wrote:
Ken Foskey schreef:
Mathew Snyder:

Is there an easy way to determine if an item is in an array without
iterating through the array and comparing each element to the item
in question?
Look up grep.

That still involves iterating and comparing each element, but now done
(faster) by grep.

If the array is already sorted, a binary search would be the way to go.

Otherwise you can use a loop that short-circuits by using "last" if the
item is found.


With smallish arrays, you can even use index(), after stringizing it:

$string = join $;, ('', @array, '');
index($string, "$;$item$;") >= 0 and print "found\n";

or use a regular expression:

$string = join "\n", @array;
/^$item$/m and print "found\n";


You might be wanting a hash table not an array.

Yes, that is the best answer. Especially if multiple items need to be
tested.


I ended up using hashes for what I needed. Thanks for the input.

Mathew
.

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