[Python-Dev] Call for defense of @decorators (original) (raw)

Ronald Oussoren ronaldoussoren at mac.com
Thu Aug 5 21:54:17 CEST 2004

On 5-aug-04, at 21:45, Neil Schemenauer wrote:

On Thu, Aug 05, 2004 at 09:28:13PM +0200, Ronald Oussoren wrote:

On 5-aug-04, at 21:17, Gustavo Niemeyer wrote:

def funcname(...): ... funcname.signature = "v@:@i"

That should be workable for this specific example. Even nicer if '' is bound to the last function defined. class SomeClass(objc): def funcname(...): ... .signature = "v@:@i" The objc metaclass could take the 'signature' function attribute and transform the function. It wouldn't work for the objc.accessor example. The objc.accessor function/decorator deduces the right kind of signature from the name and arguments of the function. Can't the metaclass do that?

Not every method is a property accessor. The metaclass does calculate a default signature (all arguments are objects and the result is an object) when it doesn't have better information (such as the signature of a method with the same name in a superclass). Sadly enough that isn't good enough for property setters. Some parts of Cocoa require that a setter returns 'void'.

I'm trying to push the automatic detection of the right signature as far as I can get to avoid having to use explicit annotations in user code, but sometimes you just cannot avoid adding annotations.

Ronald

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