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Re: "forEach:" and manual deletion

> From vlad!mark Wed Jul 18 20:10:39 1990

(This got pushed behind my mail-horizon, so it waited until I was
 cleaning out the mailbox during the second grand-compile of the day.)

> I advocate that the loop that Smalltalk's "forEach:" translates to
> delete (or destroy?) the "while_Stepper" after the close of the loop.
> By the time you exit the loop, the stepper is necessarily exhausted,
> so it's hard to see what use it would be to anyone.  This would not be
> a strictly upwards compatable change, but I strongly suspect it would
> actually be compatable with all the code we actually have.  Does
> anyone know of any examples where a stepper is used (or even held
> onto) after being stepped to exhaustion?

The only problem I can see is with the idiom for "step along until you
find what you're looking for or run out of candidates".  One natural
C/C++ idiom would be to break from the loop, then ask the stepper whether
it's exhausted.

What's the smalltalk idiom?   As I recall, breaks are a pain in Smalltalk.
If, as I suspect, it is something else entirely, that translates to something
reasonable in C++, I see no other reason not to make stepper deletion

(Yay!  One less thing for the GC to worry about.)