[TYPES] Generalised Covariant and Contravariant inference rules

[Aaron Gray]

I am looking for a paper I cannot seem to find anymore that if I remember
correctly gives or hints at a generalised scheme for describing covariant
and contravariant type inference rules.

Many thanks in advance,

Aaron
-- 
Aaron Gray

Independent Open Source Software Engineer, Computer Language Researcher,
Information Theorist, and amateur computer scientist.