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From: Stefan Monnier <monnier@iro.umontreal.ca>
To: help-gnu-emacs@gnu.org
Subject: Re: Why is booleanp defined this way?
Date: Sat, 18 Apr 2015 01:03:23 -0400	[thread overview]
Message-ID: <jwvd232t4hf.fsf-monnier+gnu.emacs.help@gnu.org> (raw)
In-Reply-To: 87bnimm6wy.fsf@kuiper.lan.informatimago.com

>> Elisp does not have a proper boolean type; unlike say symbols with
>> symbolp, strings with stringp, numberp -- some union of numeric types etc.
>> However programmers need boolean in their ontology even if (and even more if)
>> the language does not support it.
> Well, if you go this way, elisp doesn't have proper types at all!!!

I think he was alluding to the difference between the types that
`typeof' might recognize and those that are more like unions of other types.

> deftype, typep, subtypep are all defined in cl.el and as such, "frowned
> upon" by the PTB.

cl-deftype, cl-typep, ... are alive and well and not frowned upon.


        Stefan


  reply	other threads:[~2015-04-18  5:03 UTC|newest]

Thread overview: 33+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <mailman.946.1429302909.904.help-gnu-emacs@gnu.org>
2015-04-17 20:55 ` Why is booleanp defined this way? Pascal J. Bourguignon
2015-04-17 23:20 ` Barry Margolin
2015-04-17 23:30   ` Emanuel Berg
2015-04-18  0:43     ` Pascal J. Bourguignon
2015-04-18  3:13       ` Barry Margolin
2015-04-18  3:12     ` Barry Margolin
2015-04-18  2:01 ` Rusi
2015-04-18  2:23   ` Emanuel Berg
2015-04-18  2:33     ` Rusi
2015-04-18  2:55       ` Emanuel Berg
2015-04-18  3:11         ` Barry Margolin
2015-04-18  3:35           ` Rusi
2015-04-18  4:56             ` Barry Margolin
2015-04-19 23:08               ` Emanuel Berg
2015-04-19 23:00             ` Emanuel Berg
2015-04-18 21:24           ` Emanuel Berg
2015-04-18  7:52         ` Marcin Borkowski
     [not found]         ` <mailman.997.1429343558.904.help-gnu-emacs@gnu.org>
2015-04-18 12:43           ` Rusi
2015-04-18  4:09       ` Pascal J. Bourguignon
2015-04-18  5:00         ` Rusi
2015-04-18  3:50   ` Pascal J. Bourguignon
2015-04-18  5:03     ` Stefan Monnier [this message]
2015-04-17 20:34 Marcin Borkowski
2015-04-17 20:49 ` Jorge A. Alfaro-Murillo
     [not found] ` <mailman.962.1429303822.904.help-gnu-emacs@gnu.org>
2015-04-17 23:06   ` Emanuel Berg
2015-04-18  0:41     ` Pascal J. Bourguignon
2015-04-18  1:06       ` Emanuel Berg
2015-04-18  1:23         ` Pascal J. Bourguignon
2015-04-18  7:44         ` Marcin Borkowski
2015-04-18  8:37         ` Stefan Nobis
2015-04-19 23:15           ` Emanuel Berg
2015-04-18  2:37 ` Drew Adams
2015-04-18  6:13 ` Tassilo Horn

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