Funny that this question came up today, as I just had to figure this out on my own. I needed to exclude a list of items from a search, so I immediately made a list of the items:

my @items = qw (one two three etc);

but then I was stumped. Looping through the whole list every time to detect a match seems not to be an optimal method. And writing:

my %items = ( one=>1, two=>1, three=>1 );

doesn't feel very good either.

Map to the rescue!

my %items = map {$_ => 1} qw (one two three);

I'm still fairly new to map, so I'm kinda happy that I found that one on my own... Take note, fellow acolytes! :)

++jsegal

In reply to Re: Re: Set Operators by Notromda
in thread Set Operators by Anonymous Monk

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