def main():
fac5 = dedent('''\
;; factorial : number -> number
;; to calculate the product of all positive
;; integers less than or equal to n.
(letrec ((fact
(lambda (x)
(if (= x 0)
1
(* x (fact (- x 1)))))))
(fact 5))
''')
evenodd = dedent('''\
(letrec ((even?
(lambda (n)
(if (zero? n)
#t
(odd? (- n 1)))))
(odd?
(lambda (n)
(if (zero? n)
#f
(even? (- n 1))))))
(even? 88))''')
e = fac5
print('; original')
print(e)
print('; parsed')
e_parsed = parse(e)
print(pretty(e_parsed))
print('; ast')
e_ast = ast(e)
print(e_ast)
print('; cps ast')
e_cps = T_c(e_ast, halt)
print(e_cps)
gen = CodeGenerator()
print(gen.code_gen(T_c(e_ast, gen.retExp)))
return 0
def ast(txt):
return to_exp(parse(txt))