If the hash table is like: $hash{"String"}=1;, then if there is a hash collision, Perl compares the strings. All you need to know is if the string's key exists or is defined. Leave the "1" value out of the test, just look at the key. Different strings can indeed hash to the same hash value (which means hash "bucket number"). So a bucket can have more than one string/value pair.

At one time, I knew the hash doubling algorithm, but I've forgotten and it also periodically changes. But when "too many" strings hash to the same bucket, Perl will increase the hash size to make more buckets and spread things out more. This all happens automatically and is fast.

In reply to Re^2: Generating Unique numbers from Unique strings by Marshall
in thread Generating Unique numbers from Unique strings by rjohn1

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