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#73853
Should and-let* become a synonym for when-let*?
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Message #124 received at 73853 <at> debbugs.gnu.org (full text, mbox):
Stefan Monnier <monnier <at> iro.umontreal.ca> writes:
> The only natural semantics for something like when-let is the
> "sequential" bindings of `let*`. The `let` and `letrec` semantics are
> "unnatural" here, so we should have only the `let*` semantics.
I do not see an if-let where condition testing return values are
referenced in THEN, but conditions are independent and exchangeable, as
necessarily unnatural. Even when the implementation:
> [...] to something like:
>
> (when-let* ((t1 (fooa))
> (t2 (foob))
> ...)
> (let ((a t1)
> (b t2)
> ...)
> (bar)))
would not be as straightforward as for `if-let*'.
> So coders who "simplify" `when-let*` to `when-let` when the * version is
> not needed, would in reality just pessimize their code.
The other side is readability, like for `let' vs. `let*'. In my
experience condition not too seldom are independent from each other. I
would be able to make that explicit for the human reader.
But if all of you guys don't like the idea then ...ok, so it be.
> I'll let you guess where I stand w.r.t to naming of `when-let` vs
> `when-let*`, based on the fact that I originally implemented `dlet` with
> the semantics of `let*`. 🙂
Your timing of mentioning such things still has an epsilon of room for
improvement.
Michael.
This bug report was last modified 141 days ago.
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