Re: Extended modal types

["Robert I. Eachus" <rieachus@attbi.com>]

Florian Weimer wrote:


> The modulus has to be static, that's why modular types aren't
> extremely useful even in this context.


You are probably thinking of public-key encryption where the keys and 
modulii are too big for ordinary modular types anyway.   I was thinking 
of many algorithms that use modular arithmetic to introduce 
non-linearity, for example multiplying two four-bit nibbles mod 17.  In 
cases like this, the modulus is a static part of the algorithm 
definition, and needs to be prime for invertability.

Similarly, hashing tables often use the sum of the character values mod 
the size of the hash table to generate a hash location.