[ProofPower] Theorem QA

[Rob Arthan]

The scripts for the ProofPower mathematical case studies have a little tool called "check_thms" which does a quality assurance check on the the theorems in a theory. It checks against:

a) Theorems with free variables. Typically this means you forgot an outer universal quantifier. Later on you will be puzzled when tools like the rewriting tools think you don't want the free variables to be instantiated.

b) Theorems with variables bound by logical quantifiers (universal, existential and unique existential) that are not used in the body of the abstraction. This happens for various reasons (often hand in hand with (a)). It is misleading for the reader and can be confusing when you try to use the theorem.

It outputs a little report on any problems it finds.

I am considering putting a bug-fixed and documented version of check_thms in the next working release of ProofPower. Any comments or suggestions for other things to check for would be welcome. This is currently just for HOL, but I could do something similar for Z too.

Regards,

Rob.