prove_abs_fn_one_one : thm -> thm
STRUCTURE
SYNOPSIS
Proves that a type abstraction function is one-to-one (injective).
DESCRIPTION
If th is a theorem of the form returned by the function define_new_type_bijections:
   |- (!a. abs(rep a) = a) /\ (!r. P r = (rep(abs r) = r))
then prove_abs_fn_one_one th proves from this theorem that the function abs is one-to-one for values that satisfy P, returning the theorem:
   |- !r r'. P r ==> P r' ==> ((abs r = abs r') = (r = r'))

FAILURE
Fails if applied to a theorem not of the form shown above.
SEEALSO
HOL  Kananaskis-13