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Re: A little tip [message #177511 is a reply to message #177454]

Tue, 03 April 2012 13:52

Thomas 'PointedEars'
Messages: 701
Registered: October 2010

Karma:

Senior Member

Shelly wrote:

> On 3/30/2012 4:30 PM, Thomas Mlynarczyk wrote:
>> Shelly schrieb:
>>> $val = TRUE;
>>
>>> $val &= TRUE;
>>>
>>> which is identical to
>>>
>>> $val = $val && TRUE;
>>
>> No. &= is a bitwise operator while && means the logical AND operator. So
>> when you do $val &= TRUE, PHP is trying to do TRUE & TRUE, but since
>> bitwise operators only work with integers, TRUE is first coerced into
>> the integer 1. So the operation ends up as 1 & 1 yielding the integer 1.
>> Thus, $val = 1. The === operator checks the type of the operands which
>> are int and bool and thus not the same, while == tries to convert the
>> operands into something "comparable" and since they are both "truish"
>> the result is TRUE here.
>
> Thank you. That makes a lot of sense. So, what I have to do if I want
> to use === is to use the expanded form
>
> $val = $val && TRUE;

You keep missing the point. That is _not_ "the expanded form" of anything.
`&=' and `&&' are *different* operators; the first one is a *bitwise*
operator, the second is a *logical* (boolean) one.

In that sense,

x = x & 1;

is "the expanded form" of

x &= 1;

<http://php.net/operators>

Please do not full-quote.

PointedEars
--
> If you get a bunch of authors […] that state the same "best practices"
> in any programming language, then you can bet who is wrong or right...
Not with javascript. Nonsense propagates like wildfire in this field.
-- Richard Cornford, comp.lang.javascript, 2011-11-14

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[Message index]

		A little tip By: Shelly[1] on Fri, 30 March 2012 17:02
		Re: A little tip By: Jerry Stuckle on Fri, 30 March 2012 17:20
		Re: A little tip By: Shelly[1] on Fri, 30 March 2012 18:18
		Re: A little tip By: Jerry Stuckle on Fri, 30 March 2012 20:19
		Re: A little tip By: Thomas Mlynarczyk on Fri, 30 March 2012 20:30
		Re: A little tip By: Doug Miller on Fri, 30 March 2012 20:55
		Re: A little tip By: Shelly[1] on Fri, 30 March 2012 20:55
		Re: A little tip By: Jerry Stuckle on Fri, 30 March 2012 21:07
		Re: A little tip By: Jerry Stuckle on Sat, 31 March 2012 14:05
		Re: A little tip By: Shelly[1] on Sat, 31 March 2012 15:27
		Re: A little tip By: Thomas 'PointedEars' on Tue, 03 April 2012 13:52
		Re: A little tip By: Shelly[1] on Tue, 03 April 2012 14:20
		Re: A little tip By: Doug Miller on Fri, 30 March 2012 19:36
		Re: A little tip By: Jerry Stuckle on Fri, 30 March 2012 20:21
		Re: A little tip By: Doug Miller on Fri, 30 March 2012 20:52
		Re: A little tip By: Jerry Stuckle on Fri, 30 March 2012 21:08
		Re: A little tip By: Shelly[1] on Fri, 30 March 2012 21:22
		Re: A little tip By: Mr. B-o-B on Fri, 30 March 2012 23:00
		Re: A little tip By: Scott Johnson on Sat, 31 March 2012 03:33
		Re: A little tip By: Shelly[1] on Fri, 30 March 2012 21:20
		Re: A little tip By: Thomas 'PointedEars' on Tue, 03 April 2012 13:56
		Re: A little tip By: Shelly[1] on Tue, 03 April 2012 14:20
		Re: A little tip By: Michael Fesser on Sat, 31 March 2012 03:04
		Re: A little tip By: Jerry Stuckle on Sat, 31 March 2012 03:31
		Re: A little tip By: Scott Johnson on Sat, 31 March 2012 03:35
		Re: A little tip By: Jerry Stuckle on Sat, 31 March 2012 03:53
		Re: A little tip By: Doug Miller on Sat, 31 March 2012 11:58
		Re: A little tip By: Jerry Stuckle on Sat, 31 March 2012 13:05
		Re: A little tip By: alvaro.NOSPAMTHANX on Mon, 02 April 2012 07:42
		Re: A little tip By: M. Strobel on Mon, 02 April 2012 08:22
		Re: A little tip By: Shelly[1] on Mon, 02 April 2012 12:15
		Re: A little tip By: M. Strobel on Mon, 02 April 2012 12:27
		Re: A little tip By: Shelly[1] on Mon, 02 April 2012 13:40
		Re: A little tip By: M. Strobel on Mon, 02 April 2012 21:43

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