[KiLLeR.]

What's mean the "!!" operator?

[klippy]

It's not a single operator, but negation operator "!" being done twice. You would want to use that when you want to coerce a cell into a boolean, following the rule that 0 = false, anything else = true.

!!(0) == false
!!(1) == true
!!(42) == true
!!(-69) == true

This way you are making sure that your boolean is either "true" or "false" and not bool:420 for example. That's good because some people prefer to do "if(variable == true)" instead of "if(variable)", which won't give correct results if you don't "normalize" your boolean value.

[KiLLeR.]

So it will return always 0 or 1?

Thanks you! ;p

[PRoSToTeM@]

You can also do "!= 0" to cast integer to bool.

[EFFx]

PHP Code:

!(g_admin[id]) 


It means if the user is not Admin

PHP Code:

!!(g_admin[id]) 


It means If is user Admin

It just mean the opposite. Am I right?

[KiLLeR.]

PHP Code:

!!(g_admin[id]) 


As far as i understood it means that will return 0 if is 0 and 1 if is anything different from 0. This is a way to cast integer variable to bool variable.

[fysiks]

Originally Posted by EFFx PHP Code: !(g_admin[id])  It means if the user is not Admin PHP Code: !!(g_admin[id])  It means If is user Admin It just mean the opposite. Am I right?

That entirely depends on what g_admin[id] contains. If it is user flags then no, that will not work. You should always use is_user_admin() if you want to know if they are an admin (unless, of course, you fully understand how flags work and you need something different than is_user_admin() provides).

[EFFx]

Well, before I readed that post I tested if it works and got what you said. It was just an example for explain what I understood. Guess it works only with intergers and booleans.

[PRoSToTeM@]

Originally Posted by EFFx Well, before I readed that post I tested if it works and got what you said. It was just an example for explain what I understood. Guess it works only with intergers and booleans.

With float too.

[fysiks]

Using this on a boolean makes absolutely no sense since it's a double negative and will always return the original value. It's only relevant if you are trying to convert a non-boolean to a boolean value.