I want a set.

I think the best way is to use a hash to implement a set by using the existant keys to represent the current members of the set.

My current strategy is along the lines of: 

my %set;
sub contains($) { return exists $set{$_[0]} }
sub add($) { $set{$_[0]} = 1 }
sub all($) { return [keys %set] }

[download]

(I'm not actually using subs -- just for clarity.)

Is this approach the simplest way?

Is there a better approach avoiding the assignment for the add? Something like create $set{'foo'}?

I think I don't need the hash entries to be defined. I just need them to exist. (If you iterate over keys it will still return entries that have existant but undefined values right?)

-Andrew.

Andrew Tomazos  |  andrew@tomazos.com  |  www.tomazos.com

In reply to Hash Set by tomazos

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