Implementation of the call-by-value operational semantics of a recursive language REC
command syntax: interp [list-of-variables] [list-of-functions] program
example1.txt if (z) then x+y else 0
example2.txt Recursive function f1(x) = f(x)+1
example3.txt Function f2(f(1(x)) = 1 that illustrates call-by-value function evaluation
example4.txt Fibonnaci fib(x) = fib(x-1) + fib(x-2)