Re: How can I display a unique array if it contains some repeated elements

in reply to How can I display a unique array if it contains some repeated elements

a sub to get both unique and not:

@array1 = (1,1,2,3,3,4);
#unique
print unique(@array1);

#not
print unique(\@array1);

sub unique{
my (%seen, $array);
($array)=@_;
if(@$array){return grep{$seen{$_} ++} @$array;}
else{return grep{ ! $seen{$_} ++} @_;}
}
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Re: Answer: How can I display a unique array if it contains some repeated elements by halley (Prior) on Aug 14, 2003 at 21:47 UTC
Okay, that's a really bad idea. You're naming a sub suggestively and then offering two OPPOSITE functionalities. You're expecting the caller to choose the desired action with an UNRELATED and NON-MNEMONIC distinction like `ref($_[0])` vs `not ref($_[0])`. What if you send a plain `@array1` and the zeroth element is an array ref? You might want to get a unique set of array refs, but this function's not going to help there. -- `[ e d @ h a l l e y . c c ]`	[reply] [d/l] [select]

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Re: Answer: How can I display a unique array if it contains some repeated elements
by halley (Prior) on Aug 14, 2003 at 21:47 UTC

You're expecting the caller to choose the desired action with an UNRELATED and NON-MNEMONIC distinction like ref($_[0]) vs not ref($_[0]).

What if you send a plain @array1 and the zeroth element is an array ref? You might want to get a unique set of array refs, but this function's not going to help there.

--
[ e d @ h a l l e y . c c ]

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