Re: Constructor -- lambda expression

On 05/29/2010 04:07 PM, Jan Moringen wrote:
> Hi Frank.
>
>> Another question:
>>
>> (defclass foo ()
>>    ((bar :initform (lambda () (make-vector 10 nil)))))
>>
>> (make-instance 'foo)
>> ;; results in [object foo "foo" (lambda nil (make-vector 10 nil))]
>>
>> Isn't the lambda expression of the :initform supposed to be evaluated at
>> instantiation time?
>
> I'm not entirely sure, but I think that behavior has been obsoleted.

It used to do that, but it is non-standard, and RMS wanted it removed.

It is supposed to instead be something like:

(defclass foo ()
    ((bar :initform (make-vector 10 nil)))

but I haven't looked up the specifics of how that all is supposed to 
work, nor tried to make it do the right thing.

Eric

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