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From: Mark Oteiza <mvoteiza@udel.edu>
To: Michael Heerdegen <michael_heerdegen@web.de>
Cc: Emacs developers <emacs-devel@gnu.org>,
	Tino Calancha <tino.calancha@gmail.com>
Subject: On the naming/behavior of {if, when}-let (was Re: Anaphoric macros: increase visibility)
Date: Sat, 14 Jan 2017 21:24:12 -0500	[thread overview]
Message-ID: <878tqd12nn.fsf_-_@udel.edu> (raw)
In-Reply-To: <87k29xqhqp.fsf@web.de> (Michael Heerdegen's message of "Sun, 15 Jan 2017 01:39:10 +0100")


Michael Heerdegen <michael_heerdegen@web.de> writes:
> I sometimes think that
> `if-let*' would be a better name for `if-let' because bindings can refer
> (and naturally most of the time do) refer to other bindings.

There was a thread some time ago (I'd have to go dig for it) where
someone asked why the names lacked the *.  Seeing how they are
implemented on top of let*, this should be a no brainer, right?

Further, I think it's even more bizarre that if-let and when-let grew
the single tuple special case, where one can write

  (if-let (foo bar) (message "%S" foo) (message "oh no"))
          ^^^^^^^^^

What makes these binding things special? May as well add brackets and
whatever else from other lisps.

… and yet there is no _actual_ if-let to the effect of:

  (let ((a foo)
        (b bar))
    (if (and a b) 'yes 'no))

Though, for the above, I remember there being an argument against this
being useful.  IDK, I've written things like this before.

> I also
> often think that `and-let' (or `and-let*' ...)  would be a better name
> for `when-let' (because the expressions for the bindings are `and'ed,
> sot the whole thing feels more like `and' to me).

I'd also like an and-let* (presumably aliased to when-let*).



  reply	other threads:[~2017-01-15  2:24 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-01-13  8:39 Anaphoric macros: increase visibility Tino Calancha
2017-01-13 19:48 ` Michael Heerdegen
2017-01-14  2:30   ` Rolf Ade
2017-01-14  2:48     ` Rolf Ade
2017-01-14  3:03     ` Noam Postavsky
2017-01-14  4:13       ` Richard Copley
2017-01-14  5:27   ` Tino Calancha
2017-01-15  0:39     ` Michael Heerdegen
2017-01-15  2:24       ` Mark Oteiza [this message]
2017-01-15  2:26       ` Michael Heerdegen
2017-01-15 10:24       ` Tino Calancha
2017-01-15 15:32         ` Stefan Monnier
2017-01-16  2:44           ` Tino Calancha
2017-01-16  3:59             ` Stefan Monnier
2017-01-14  6:25   ` Dmitri Paduchikh
2017-01-14  7:56     ` Tino Calancha
2017-01-14 10:15       ` Dmitri Paduchikh
2017-01-15  0:29         ` Michael Heerdegen
2017-01-15  2:03           ` Dmitri Paduchikh
2017-01-15  2:16             ` Michael Heerdegen

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