[Tutor] How can I have type "function" in my script?

xancorreu xancorreu at gmail.com
Tue May 8 20:31:41 CEST 2012

Al 08/05/12 19:36, En/na Alan Gauld ha escrit:
> On 08/05/12 11:23, xancorreu wrote:
>> It works with
>> c = Tag("twice", type(lambda x: x), lambda x: 2*x)
>> but I want to specify the type of (lambda x: x) **manually** as I do
>> with str in b
> Unfortunately we don't always get what we want.
> You have to use type for functions.
> You can use a very simple function, but you need to use type()...
> type(lambda : 0)
> is about as simple as you can do it with lambda...

A much pain for me. I think there should be a type.function avaliable in 
python, like str, int, etc. exists. I think as python is O-O language 
and have (or at least the page says that) higher-order function, I 
should could type:

isinstance(2, function)

like I do

isinstance(2, int)

Do you understand my reasoning?
> However, you still haven't said why you want the type. It's very 
> unusual in Python to need explicit type information. If we knew what 
> you were trying to do with it we might be able to offer a more 
> pythonic way to go about it.

Yes, I know that the pythonic way is to not define types in variables. 
The variables are free while there is no assign to these. I need type 
because I want to implement Tag as triple of name, type and value. I 
want to differentiate between a tag with type str and value "today" and 
a tag with tag with type data and value "today".

That's all.

Thanks for the answer.

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