Re: Differences between [[Class]] and constructor

Path	csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!us.feeder.erje.net!news2.arglkargh.de!news.mixmin.net!weretis.net!feeder1.news.weretis.net!news.solani.org!.POSTED!not-for-mail
From	Thomas 'PointedEars' Lahn <PointedEars@web.de>
Newsgroups	comp.lang.javascript
Subject	Re: Differences between [[Class]] and constructor
Date	Tue, 02 Jun 2015 22:58:02 +0200
Organization	PointedEars Software (PES)
Lines	32
Message-ID	<6733032.WIyCHQfpTH@PointedEars.de> (permalink)
References	<ct69cmFtvojU1@mid.uni-berlin.de>
Reply-To	Thomas 'PointedEars' Lahn <cljs@PointedEars.de>
Mime-Version	1.0
Content-Type	text/plain; charset="UTF-8"
Content-Transfer-Encoding	8Bit
X-Trace	solani.org 1433278847 29629 eJwNycEBwCAMAsCVqhLEcWoM+4+g37sYbMwJBhEOn169a03xiXlKr4rAchL+MDKlv5o3NlUXDakQ+w== (2 Jun 2015 21:00:47 GMT)
X-Complaints-To	abuse@news.solani.org
NNTP-Posting-Date	Tue, 2 Jun 2015 21:00:47 +0000 (UTC)
User-Agent	KNode/4.14.2
X-User-ID	eJwFwQkBACAIA8BKiGNgHOXpH8E721xMB42wsXmZepQqaDXXK73sASJp9HPCp5DyelW1xHCXOgvj+0Z25Ac94hVl
Cancel-Lock	sha1:qa8KUIVTbmrtma+ElH8orhg4/Fc=
X-NNTP-Posting-Host	eJwFwQEBwDAIAzBNh7YcOYOBfwlL6PrUAVHgci9WGEuDNquQTWKncQZR/2kp/JaLuWPMBySVEVM=
Xref	csiph.com comp.lang.javascript:27967

Show key headers only | View raw

Stefan Ram wrote:

>   I have observed that the class ([[Class]]) name

That is _not_ the “class name”, it is the value of the internal “[[Class]]” 
property of values.  “[[Class]]” is purely a Specification mechanism and 
does not need to be implemented in a way other than to satisfy the 
algorithms of the Specification.

>   and the constructor name of an object often is the same!

Often, but not always.  As specified.

> function className( object )
> { return 0,
>   Object.prototype.toString.call( object ).
>   replace( "\[object ", "" ).replace( "\]", "" ); }

This is written shorter, less error-prone, more efficient, and actually 
readable

  (({}).toString.call(object).match(/\[object\s+(.+)\s*\]/) || [])[0]

> let n = new Number( 3.14 );

  var n = Math.PI;

-- 
PointedEars
FAQ: <http://PointedEars.de/faq> | SVN: <http://PointedEars.de/wsvn/>
Twitter: @PointedEars2 | ES Matrix: <http://PointedEars.de/es-matrix>
Please do not cc me. / Bitte keine Kopien per E-Mail.

Back to comp.lang.javascript | Previous | Next — Next in thread | Find similar | Unroll thread

Thread

Re: Differences between [[Class]] and constructor Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-02 22:58 +0200
  Re: Differences between [[Class]] and constructor Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-06-02 23:07 +0200

csiph-web