path: root/sketch.py

class SyntaxObj(object):
    pass

class EvalObj(SyntaxObj):
    def __str__(self):
        return "#<Object>"

class ValObj(EvalObj):
    def __str__(self):
        return "#<Value>"

class NumberObj(ValObj):
    def __str__(selfl):
        return "#<Number>"

class IntObj(NumberObj):
    def __init__(self, num):
        self.val = int(num)
    def __str__(self):
        return "#<Integer>"

class FloatObj(NumberObj):
    def __init__(self, num):
        self.val = float(num)
    def __str__(self):
        return "#<Float>"

class StringObj(ValObj):
    def __init__(self, string):
        self.val = string

    def __str__(self):
        return "#<String>"
class BoolObj(ValObj):
    def __init__(self, b):
        self.val = b
    def __str__(self):
        return "#<Boolean>"

class OptObj(EvalObj):
    pass

class ProcObj(OptObj):
    def __init__(self, prog, env = None):
        self.prog = prog
        self.env = env
    def __str__(self):
        return "#<Procedure>"

class SpecialOptObj(OptObj):
    def prepare(self, pc):
        pass
    def call(self, arg_list, pc, envt, cont):
        pass

class BuiltinProcObj():
    def __init__(self, f, ext_name):
        self.handler = f
        self.ext_name = ext_name
    def __str__(self):
        return self.ext_name
    def call(self, arg_list):
        return self.handler(arg_list)

def to_bool(obj):
    if obj.val == False:
        return BoolObj(False)
    else:
        return BoolObj(True)

class _builtin_if(SpecialOptObj):
    def prepare(self, pc):
        self.state = 0 # prepare
        # TODO: check number of arguments 
        return (True, False, False)
        # Delay the calculation
    def pre_call(self, arg_list, pc, envt, cont):
        self.state = 1 # calling
        print "Received if signal: " + str(arg_list[0].val)
        print "And it is regared as: " + str(to_bool(arg_list[0]).val)
        if (to_bool(arg_list[0])).val:
            return ((False, True, False), True) # Re-eval
        else:
            return ((False, False, True), True) # Re-eval
    def post_call(self, arg_list, pc, envt, cont):
        return (arg_list[0], False)

    def call(self, arg_list, pc, envt, cont):
        if self.state == 0:
            return self.pre_call(arg_list, pc, envt, cont)
        else:
            return self.post_call(arg_list, pc, envt, cont)
    def __str__(self):
        return "#<builtint opt if>"

class _builtin_lambda(SpecialOptObj):
    def prepare(self, pc):
        # TODO: check number of arguments 
        return [ False, False ]

class IdObj(SyntaxObj):
    def __init__(self, string):
        self.name = string
    def __str__(self):
        return "#<Identifier>"
    def get_name():
        return self.name

class Tokenizor():

    def __init__(self):
        self.data = ""
        self.tokenized = list()
        self.extended_chars = "!$%&*+-./:<=>?@^_~"

    def is_identifier(self, string):
        if string[0].isdigit(): return False
        for i in string[1:]:
            if not (i<