FUN_EQ_CONV : conv
STRUCTURE
Conv
SYNOPSIS
Equates normal and extensional equality for two functions.
DESCRIPTION
The conversion FUN_EQ_CONV embodies the fact that two functions are equal precisely when they give the same results for all values to which they can be applied. When supplied with a term argument of the form f = g, where f and g are functions of type ty1->ty2, FUN_EQ_CONV returns the theorem: 
   |- (f = g) = (!x. f x = g x)
where x is a variable of type ty1 chosen by the conversion.
FAILURE
FUN_EQ_CONV tm fails if tm is not an equation f = g, where f and g are functions.
USES
Used for proving equality of functions.
SEEALSO
EXT, X_FUN_EQ_CONV
HOL  Kananaskis-14