Path: csiph.com!usenet.pasdenom.info!weretis.net!feeder4.news.weretis.net!npeer.de.kpn-eurorings.net!npeer-ng0.de.kpn-eurorings.net!newsfeed.arcor.de!newsspool3.arcor-online.net!news.arcor.de.POSTED!not-for-mail
Content-Type: text/plain; charset="UTF-8"
Message-ID: <1639100.PjNAD8PV0k@PointedEars.de>
From: Thomas 'PointedEars' Lahn <PointedEars@web.de>
Reply-To: Thomas 'PointedEars' Lahn <usenet@PointedEars.de>
Organization: PointedEars Software (PES)
Date: Sat, 25 May 2013 07:00:33 +0200
User-Agent: KNode/4.10.2
Content-Transfer-Encoding: 8Bit
X-Face: %i>XG-yXR'\"2P/C_aO%~;2o~?g0pPKmbOw^=NT`tprDEf++D.m7"}HW6.#=U:?2GGctkL,f89@H46O$ASoW&?s}.k+&.<b';Md8`dH6iqhT)6C^.Px|[=M@7=Ik[_w<%n1Up"LPQNu2m8|L!/3iby{-]A+#YE}Kl{Cw$\U!kD%K}\2jz"QQP6Uqr],./"?;=4v
Face: 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
Subject: Re: !0 versus true
Newsgroups: comp.lang.javascript
References: <gMWdnU1mmO68hwPMnZ2dnUVZ_sqdnZ2d@westnet.com.au> <4493946.nSsM8AgQI3@PointedEars.de> <a1Pnt.5879$OS5.4813@newsfe24.iad> <knooc3$qpi$1@dont-email.me>
MIME-Version: 1.0
Lines: 37
NNTP-Posting-Date: 25 May 2013 07:00:38 CEST
NNTP-Posting-Host: 3e04067d.newsspool3.arcor-online.net
X-Trace: DXC=4I@\E3<bSGZ[7Non7UCi8UMcF=Q^Z^V3X4Fo<]lROoRQ8kF<OcfhCO[?F<P;FJ26_RDZm8W4\YJN\b@mF9jNikdUW@XamafOF][NXj43QJ52<Q
X-Complaints-To: usenet-abuse@arcor.de
Xref: csiph.com comp.lang.javascript:19952

Denis McMahon wrote:

> On Fri, 24 May 2013 12:17:28 -0700, Daniel Pitts wrote:
>> Yes, but if (x === true) can not be reduced to if (x).
> 
> How about if(x===!0)

I think that was the point of the comment.  However, it is not a good idea.  
This is not just an equivalent expression.  Since we must not assume 
optimization, it includes an *additional operation* *each* time this 
statement is executed.  For what?  Two octets less loaded the *one* time it 
is loaded – a time savings of 0.3 ms in the *worst* case (56k dial-up 
modem)?

<http://samizdat.mines.edu/howto/HowToBeAProgrammer.html#id2789469>

> if "!0" is identical to "true" then the test "x===true" is identical to
> the test "x===!0"

And +!1 is equivalent to 0.  We still write only 0; not because it is 
shorter, but because it is *less complex*, i.e. *faster*.

> Where I use "is identical to" in the sense of "===", whereas I would use
> "is equivalent to" in the sense of "=="

Making up your private terminology is not helpful.  An *expression* is 
/equivalent/ to another *expression* if both expressions are evaluated to 
the same value under the same conditions; one expression can be exchanged 
with the other without affecting the outcome of expressions in which they 
are used.  A *value* is /identical/ to another *value* if both values are 
the same.

-- 
PointedEars

Twitter: @PointedEars2
Please do not Cc: me. / Bitte keine Kopien per E-Mail.