question about foreach, opApply, and delegates
Jerry Quinn
jlquinn at optonline.net
Mon Jun 8 07:04:08 PDT 2009
downs Wrote:
> Jerry Quinn wrote:
> > Hi, all. I find myself a little confused about how foreach, opApply, and delegates interact according to the docs.
> >
> > Foreach on an aggregate will use the opApply call (assuming ranges aren't being used). So if we use a simple example below, what exactly is the delegate that is passed to opApply?
>
> > The docs say a delegate is a pairing of an object reference and a function, where the object is passed as the 'this' parameter to the function. But that doesn't seem to be the case here.
>
> If the docs say that, they're wrong.
>
> Generally speaking, a delegate is a pairing of a function pointer and a context, where the context can be a struct pointer, a class reference *or a stackframe*, as is the case with opApply.
>
> Hope that clears things up.
Yes, that helps. All 3 replies are basically the same, and the docs are clearly insufficient to describe what's actually happening in a delegate.
I'll file a bug.
Thanks!
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