MK_COMBThm.MK_COMB : thm * thm -> thm
Proves equality of combinations constructed from equal functions and operands.
When applied to theorems A1 |- f = g and
A2 |- x = y, the inference rule MK_COMB
returns the theorem A1 u A2 |- f x = g y.
A1 |- f = g A2 |- x = y
--------------------------- MK_COMB
A1 u A2 |- f x = g y
Fails unless both theorems are equational and f and
g are functions whose domain types are the same as the
types of x and y respectively.