def unparse(ast):
if is_boolean(ast):
return "#t" if value_of(ast) else "#f"
elif is_integer(ast):
return str(value_of(ast))
elif isinstance(ast, list):
if len(ast) > 0 and ast[0] in quote_names:
return "%s%s" % (quote_names[ast[0]], unparse(ast[1]))
else:
return "(%s)" % " ".join([unparse(x) for x in ast])
else:
return str(ast) # string, integer or Closure
def get_builtin_env():
"""Returns an environment with the builtin functions defined.
You probably want to use moolisp.interpreter.default_env instead,
which is this extended with the Moo Lisp core functions."""
return Environment({
'+': Builtin(lambda x, y: integer(value_of(x) + value_of(y))),
'-': Builtin(lambda x, y: integer(value_of(x) - value_of(y))),
'*': Builtin(lambda x, y: integer(value_of(x) * value_of(y))),
'/': Builtin(lambda x, y: integer(value_of(x) / value_of(y))),
'mod': Builtin(lambda x, y: integer(value_of(x) % value_of(y))),
'=': Builtin(lambda x, y: boolean(x == y)),
'>': Builtin(lambda x, y: boolean(x > y)),
'<': Builtin(lambda x, y: boolean(x < y)),
'>=': Builtin(lambda x, y: boolean(x >= y)),
'<=': Builtin(lambda x, y: boolean(x <= y)),
'cons': Builtin(lambda h, rest: [h] + rest),
'car': Builtin(lambda lst: lst[0]),
'cdr': Builtin(lambda lst: 'nil' if len(lst) == 1 else lst[1:]),
'list': Builtin(lambda *args: 'nil' if len(args) == 0 else list(args))
})
def eval_cond(ast, env):
for predicate, ast in ast[1:]:
p = evaluate(predicate, env)
_assert_boolean(p, predicate)
if value_of(p) is True:
return evaluate(ast, env)
