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prove_rep_fn_one_one                                           (Drule)
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prove_rep_fn_one_one : thm -> thm

SYNOPSIS
Proves that a type representation function is one-to-one (injective).

DESCRIBE
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_rep_fn_one_one th} proves from this theorem that the
function {rep} is one-to-one, returning the theorem:

   |- !a a'. (rep a = rep a') = (a = a')




FAILURE
Fails if applied to a theorem not of the form shown above.

SEEALSO
Definition.new_type_definition, Drule.define_new_type_bijections,
Drule.prove_abs_fn_one_one, Drule.prove_abs_fn_onto,
Drule.prove_rep_fn_onto.

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