where u[vi/xi] denotes the result of substituting vi for all free
occurrences of xi in u, after renaming sufficient bound variables to avoid
variable capture.
FAILURE
LIST_BETA_CONV tm fails if tm does not have the form
"(\x1 ... xn. u) v1 ... vn" for n greater than 0.
EXAMPLE
- LIST_BETA_CONV (Term `(\x y. x+y) 1 2`);
> val it = |- (\x y. x + y)1 2 = 1 + 2 : thm