splice.

Duplicated elements can be removed by using them as hash keys,

@hash{@array) = ();
@array = keys %hash;
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or by sorting and testing successive elements. If order is important, you must decide whether you want the first or last occurrance. Then you can construct a second array by pushing on elements which haven't been seen yet, $hash{$_}++ or push @unique, $_ for @array;