From: ts <decoux@...>
Date: 2001-01-19T22:53:23+09:00
Subject: [ruby-talk:9552] Re: Strange Hash behavior

>>>>> "A" == Agnot Tok <agnottok@hotmail.com> writes:

A> Can someone give a rationale?

 Because you are not in a case of perfect hashing, i.e. 2 differents
objects (in eql? sense) can give the same hash value (there is collision).

 For example these 2 strings "merged" and "Dominick" give the same hash
 value 

pigeon% ruby -e 'p "merged".hash, "Dominick".hash'
697276383
697276383
pigeon% 

 If you consider only the hash function you can't differentiate
 these 2 strings.

p.s.: this is a bad example because in ruby String#hash is not the function
used by st_lookup



Guy Decoux