Null == 0?

[Antares]

Hi!

 

I read the guide on scripting and this made me think:

 

if (foo) ...        // this will check if 'foo' has been declared or not. If the value 'foo'
            // holds is different from 0 (declared), it will return true. Otherwise it
            // will return false.

if (foo != 0) ...    // Same as above

 

Does this mean that a varable with 0 is the same as null (variable not declared)?

 

I need to store the index of an array, that can be any number between (incl) 0 and 19.

 

I have checks not to execute the array indexing, if the index is not set [ if ($var != null) ]

 

Do I have to rewrite my index variable to store numbers between 1 and 20 and when indexing the array reduce it by one?

Edited May 30, 2013 by Antares

[Emistry]

any integer variable with value of 0 is same as "not declared" ...

I have checks not to execute the array indexing, if the index is not set [ if ($var != null) ]

basically you can compare it like this....the "null" will be treat as the "character variable" with a value of 0 ( if it's not declared ) ...

 

Do I have to rewrite my index variable to store numbers between 1 and 20 and when indexing the array reduce it by one?

you mean delete the value from array ?

you can use deletearray

[Antares]

In case of random returning 0 which one will display "a"?

 

 

 

setarray .myarray[0], "a", "b", "c", "d", "e";
$foo = rand(0,4);
if($foo){
     mes .myarray[$foo];
}
 

 

 

or 

 

 

 

setarray .myarray[0], "a", "b", "c", "d", "e";
$foo = rand(0,4) + 1;
if($foo){
     mes .myarray[$foo - 1];
}
 

[Emistry]

setarray .myarray$[0], "a", "b", "c", "d", "e";
set .myarray_size,getarraysize( .myarray$ );
// $foo = rand( .myarray_size );

for( .@i = 0; .@i < .myarray_size; .@i++ )
	mes ".myarray$["+.@i+"] = "+.myarray$[.@i];
close;

 

in your case...

setarray .myarray[0], "a", "b", "c", "d", "e";
$foo = rand(0,4) + 1;
if($foo){
     mes .myarray[$foo - 1];
}

 

anyway....you dont have to check if the $foo is assigned a value or not..the array start from 0 ~ 4 ...

it will alway return the 1st value in array if your $foo isnt assigned with any value.