question about foreach, opApply, and delegates
downs
default_357-line at yahoo.de
Mon Jun 8 07:01:16 PDT 2009
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.
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