Hashing of "switch/case" selections

[dewar@gnat.com]

<<  I think Mr. Huffman and Mr. Kern might disagree..... surely a
.ZIP file is a unique hash of a given input, and one that has a
very useful difference from that original input.  Of course, IANAQCS.
>>

A zip file is simply a 1-1 mapping that may (but obviously does not always
) have a length less than the original file -- obviously if the zip file
is shorter than the original file in some cases, it will be longer inother
cases.

No one would call this a hash function in my experience. As I say, the
central point of a hash function is that it performs a many to one
mapping, that's what makes it interesting.

To call all 1-1 mappings hash functions is truly odd terminology :-)