[Dygear]

Optimizing Plugins (AMX Mod X Scripting): For Loop Comparisons

new string[256] = "something long"
for (new i=0; i<strlen(string); i++)
   //...code 

Agreed that is bad, but this:

new string[256] = "something long"
new len = strlen(string)
for (new i=0; i<len; i++)
   //...code 

Why not:

new string[256] = "something long"
for (new i = 0, len = strlen(string); i < len; i++)
   //...code 

[fysiks]

Originally Posted by Dygear Why not: new string[256] = "something long" for (new i = 0, len = strlen(string); i < len; i++)    //...code

It calls strlen() native every iteration. Same as the first code you posted. Bad.

Alos, this forum is not for asking questions. Ask in scripting help.

[Dygear]

Originally Posted by fysiks It calls strlen() native every iteration. Same as the first code you posted. Bad.

Isn't it the same as doing this?

new string[256] = "something long, that's what she said.";
new i = 0, len = strlen(string);
for (; i < len; i++)
    //...code 

Just wondering if it's different in PAWN then the other languages I use.

Originally Posted by fysiks Alos, this forum is not for asking questions. Ask in scripting help.

Sorry.

[fysiks]

Originally Posted by Dygear Isn't it the same as doing this? new string[256] = "something long, that's what she said."; new i = 0, len = strlen(string); for (; i < len; i++)     //...code Just wondering if it's different in PAWN then the other languages I use.

No, it's not the same. strlen() in that code is not inside the for() so it is not called every iteration. When strlen() is inside the for() the it is called which is slower than just accessing a value from a variable.

[Dygear]

Originally Posted by fysiks When strlen() is inside the for() the it is called which is slower than just accessing a value from a variable.

Ok, because I was under the impression that the first statement in the for loop is the initialization line.

for (initialization; condition; step)
    // Code 

for (i = 1; i <= 10; i++)
    printf("%d", i);

If what your saying is true, then this will never reach 10, it will just keep on printing out 1s for the rest of time. Does not make much sense to me.

[Greenberet]

dygear you are right.
it's more or less the same.
The difference is just the namespace.

new string[256] = "something long, that's what she said.";
new len = strlen(string);
for (new i = 0; i < len; i++)
{
// len is visible here
}
// len is still visible here 

new string[256] = "something long, that's what she said.";
for (new i = 0, len = strlen(string); i < len; i++)
{
// len is visible
}
// len isn't visible here 

[fysiks]

Oh, I didn't see that it was a comma separating new i = 0 and len declaration. I thought it was still part of the condition. Sorry.

[Dygear]

Originally Posted by Greenberet new string[256] = "something long, that's what she said."; for (new i = 0, len = strlen(string); i < len; i++) { // len is visible } // len isn't visible here

That's interesting, I never really thought about visibility, but I've also never tripped over it too.

Originally Posted by fysiks Oh, I didn't see that it was a comma separating new i = 0 and len declaration. I thought it was still part of the condition. Sorry.

Happens to all of us.