Insert unique data into array

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hi,

I am trying to create an array with unique data on the fly. how can i check if a the data i need to add to the array, already exists in the array.

Thanks in advance.

aaa

Comment on Insert unique data into array

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Re: Insert unique data into array by Joost (Canon) on Aug 14, 2004 at 11:18 UTC
The idiomatic way in perl is to use a hash to mark already inserted data: `my @data; my %seen; for (@input) { next if $seen{$_}++; push @data,$_; }` [download] using grep, that would be: `my %seen; my @data = grep { ! $seen{$_}++ } @input;` [download] update: s/make/mark/ update2: fixed bug, thanks to Happy-the-monk "What should it profit a man, if he should win a flame war, yet lose his cool?"	[reply] [d/l] [select]
Re: Insert unique data into array by Limbic~Region (Chancellor) on Aug 14, 2004 at 14:09 UTC
Anonymous Monk, If you don't want to be bothered with the details and want it to "just work", you might want to check out a couple of modules on CPAN: Array::Unique Tie::Array::Unique Cheers - L~R	[reply]