Global Variables

[doug-hines]

I want to create an array with empty elements in it. Then use various proc to change the element values. Is this even possible?

Below is the general idea of what I'm trying to do

[codebox]global string $testProcString[3] = {"", "", ""};

proc mainTestProc()
{
step01;
step02;
}

proc step01() // Modify the existing Elements
{
$testProcString[0] = "zero";
$testProcString[1] = "one";
$testProcString[2] = "two";
}

proc step02() // Print those elements to verify they stayed change
{
print $testProcString[0];
print $testProcString[1];
print $testProcString[2];

}
mainTestProc;

[/codebox]

[dbiggs]

Almost there, you need to tell the procs about the existance of the global. (I never understood why Mel requires this)

[codebox]

global string $testProcString[3] = {"", "", ""};

proc mainTestProc()
{
global string $testProcString[];
step01;
step02;
}

proc step01() // Modify the existing Elements
{
global string $testProcString[];
$testProcString[0] = "zero";
$testProcString[1] = "one";
$testProcString[2] = "two";
}

proc step02() // Print those elements to verify they stayed change
{
global string $testProcString[];
print $testProcString[0];
print $testProcString[1];
print $testProcString[2];

}
mainTestProc;
[/codebox]

[doug-hines]

I see! Thanks Biggs!

[joojaa]

QUOTE
(I never understood why Mel requires this)

most languages do.

Because it eliminates a lot of very hard to debug problems. Suppose scripter a and b use a variable $myRotationBefore and a declares it global, now unknown to programmer b this variable hjas been changed and global.

Now if the programmer b does not declare it global he has no problems, but boy would he have if it wasn't necessary. So it might never occour too him to start ooking for a global with a equal name because its quite obviously local.

Secondly if you cpy paste data blocks you could have polluted a variable used as local in that block, so it makes things easier., but this is a side effect. But a useful one.