On 05/07/2012 04:37 PM, xancorreu wrote:
> Al 07/05/12 21:07, En/na Dave Angel ha escrit:
>> On 05/07/2012 02:24 PM, xancorreu wrote:
>>> Hi,
>>>
>>> I have this script:
>>>
>>> from types import *
>>>
>> Bad idea. Once you do that, you can silently overwrite globals in your
>> own module with stuff that the current version of types happens to have
>> in it. Besides, it then becomes very hard to read your program and
>> figure out which names you really did want to import.
>>
>> If you're just getting one or two names, such as in your case, better
>> just do
>> import types
>>
>>> class Tag:
>>>
>>> def __init__(self, nom, tipus, valor):
>>> self.nom = nom
>>> self.tipus = tipus
>>> self.valor = valor
>>>
>>> def __str__(self):
>>> return "Nom: " + str(self.nom) + ", Tipus: " +
>>> str(self.tipus) + ", Valor: " + str(self.valor)
>>>
>>>
>>> def main():
>>> a = Tag("descripció", str, "primera tasca")
>>> b = Tag("unmes", str, lambda x: x+1)
>>> print(a)
>>> print(b)
>>>
>>> if __name__ == '__main__':
>>> main()
>>>
>>>
>>> All is ok, but when I substitute b = Tag("unmes", str, lambda x: x+1)
>>> for b = Tag("unmes", function, lambda x: x+1) I receive an error that
>>> function is not globally defined variable. How can I say that function
>>> is the types.function? (the type of lambda x: x+1)
>>>
>> Where's the stack trace and the exact error message?
>>
>> types.function is undefined. The types module does not expose a name
>> called 'function,' at least not in python 3.2
>>
>> The type of a lambda is<class 'function'>, so it's not clear what you
>> really want.
>>
>> Why don't you show the program as you actually run it (perhaps with both
>> versions of the b= assignment), and the output and stack trace you got.
>> Then explain just what you'd hoped to get, as output.
>>
>
> This is the code:
>
> class Tag:
>
> def __init__(self, nom, tipus, valor):
> self.nom = nom
> self.tipus = tipus
> self.valor = valor
>
> def __str__(self):
> return "Nom: " + str(self.nom) + ", Tipus: " + str(self.tipus)
> + ", Valor: " + str(self.valor)
>
> class Task:
> _nombre = 0
>
> def __init__(self):
> self.tags = []
> Task._nombre = Task._nombre + 1
> self.num = Task._nombre
>
>
> def __str__(self):
> return "Número: " + str(self.num) + ", Tags: " + str(self.tags)
>
> def main():
> a = Tag("descripció", str, "primera tasca")
> b = Tag("unmes", str, lambda x: x+1)
> c = Tag("twice", type(lambda: x: x), lambda x: 2*x)
> # en comptes de str ha de ser lambda
> print(a)
> print(b)
> print(b.valor(2))
> t = Task()
> print("Tasca 1:", t)
> t2 = Task()
> print("Tasca 2:", t2)
>
> if __name__ == '__main__':
> main()
>
>
> and it fails here:
>
> $ python3 tasques.py
> File "tasques.py", line 26
> c = Tag("twice", type(lambda: x: x), lambda x: 2*x)
> ^
> SyntaxError: invalid syntax
>
>
> Really, I want to specify "manually" the type of lambda, but it does not
> work. How to do that?
>
>
> Thanks,
>
>>> I use python3
>>>
>>>
>>> Thanks in advance,
>>> Xan.
>
>
def main():
a = Tag("descripció", str, "primera tasca")
print (a)
b = Tag("unmes", str, lambda x: x+1)
print(b)
c = Tag("unmes", "function", lambda x: x+1)
print(c)
Does that help?
--
DaveA
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