From: Rolf Ade <rolf@pointsman.de>
To: emacs-devel@gnu.org
Subject: Re: Anaphoric macros: increase visibility
Date: Sat, 14 Jan 2017 03:30:19 +0100 [thread overview]
Message-ID: <87k29y2x1g.fsf@pointsman.de> (raw)
In-Reply-To: 87wpdyivvf.fsf@web.de
Michael Heerdegen <michael_heerdegen@web.de> writes:
> We also already have `if-let' and `when-let' in "subr-x". They are like
> `aif' and `awhen' but you specify "it" explicitly.
Since you mention them ... I probably miss something obvious but from
looking at the documentation of if-let
if-let is a Lisp macro in ‘subr-x.el’.
(if-let BINDINGS THEN &rest ELSE)
Process BINDINGS and if all values are non-nil eval THEN, else ELSE.
Argument BINDINGS is a list of tuples whose car is a symbol to be
bound and (optionally) used in THEN, and its cadr is a sexp to be
evalled to set symbol’s value. In the special case you only want
to bind a single value, BINDINGS can just be a plain tuple.
and of if-when
when-let is a Lisp macro in ‘subr-x.el’.
(when-let BINDINGS &rest BODY)
Process BINDINGS and if all values are non-nil eval BODY.
Argument BINDINGS is a list of tuples whose car is a symbol to be
bound and (optionally) used in BODY, and its cadr is a sexp to be
evalled to set symbol’s value. In the special case you only want
to bind a single value, BINDINGS can just be a plain tuple.
I don't get, why there is a need for if-when?
next prev parent reply other threads:[~2017-01-14 2:30 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 [this message]
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 ` On the naming/behavior of {if, when}-let (was Re: Anaphoric macros: increase visibility) Mark Oteiza
2017-01-15 2:26 ` Anaphoric macros: increase visibility 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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