def eval(self, exp, env):
length = Special.util.length(exp)
if(length != 3):
self._error('invalid number of arguments for define')
return Nil.getInstance()
args = exp.getCdr().getCar()
body = exp.getCdr().getCdr()
if(args.isPair()):
funcName = args.getCar()
args = args.getCdr()
if(not (funcName.isSymbol)):
self._error('invalid function name')
return Nil.getInstance()
params = args
while(params.isPair()):
if(not (params.getCar().isSymbol())):
self._error('invalid parameter')
return Nil.getInstance()
params = params.getCdr()
function = Cons(Ident('lambda'), Cons(args, body))
function = function.eval(env)
env.define(funcName, function)
return Nil.getInstance()
if(args.isSymbol):
env.define(args, body.getCar().eval(env))
return Nil.getInstance()
self._error('invalid expression with define')
def eval(self, exp, env):
#sys.stdout.write('inside define.eval')
t = Special.util.length(exp)
if t < 3:
self._error("define error")
return Nil.getInstance()
elif exp.getCdr().getCar().isPair():
vars = exp.getCdr().getCar()
parms = vars.getCdr()
sym = vars.getCar()
rest = exp.getCdr().getCdr()
func = Cons(Ident("lambda"), Cons(parms, rest))
env.define(sym, func.eval(env))
return Nil.getInstance()
else:
vars = exp.getCdr().getCar()
val = exp.getCdr().getCdr().getCar()
if vars.isSymbol():
if t == 3:
env.define(vars, val.eval(env))
return Nil.getInstance()