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Posted: Tue Aug 13, 2002 7:10 pm

Hello

Is there a way of shortening this using %case or another function? Correct me if I'm wrong, but I thought multiple #IF statements like this were 'suboptimal'.

Or does it matter how I write it as long as I can understand it because the interpreter has to basically convert it to #IF regardless of whether I use %case or not?

#IF %pos( "(w)", @strx) {#VARIABLE ttemp string1}
#IF %pos( "(g)", @strx) {#VARIABLE ttemp string2}
#IF %pos( "(b)", @strx) {#VARIABLE ttemp string3}
#IF %pos( "(d)", @strx) {#VARIABLE ttemp string4}

Thanks,
Steve :)

GURU Joined: 10 Oct 2000 Posts: 4379 Location: USA

Using %case would actually end up in more lines of zScript. However, you can make it a bit faster by nesting the if's. It appears that the variable may either contain "(w)", "(g)", "(b)" or "(d)" but not more than one of these. If you nest the if's, then once one of them matches, the other won't be checked. You should also put them in the order they are most likely to be matched. So, suppose the most common occurance is that it contains "(b)", the next common one is "(g)" and then "(w)" and "(d)". In this case, you do:
#VAR ttemp %if(%pos("(b)", @strx), "string1", %if(%pos("(g)", @strx), "string2", %if(%pos("(w)", @strx), "string3", %if(%pos("(d)", @strx), "string4", ""))))

But, all in all, it really shouldn't make a big difference if you turn it into a case statement or a bunch of if's. In reality, a case is just a specialized form of nested if statements. At the end, when translated into machine code, both still need to jump around in the code, which means that the processor stack must be cleared each time, which is what really causes the slowdown, but it is still not noticeable.

Kjata

Posted: Tue Aug 13, 2002 8:49 pm

Thankyou Kjata, I didn't realise %if existed - lots of possibilities here. It works a treat, but I have just one further question.

#VAR ttemp %if(%pos("(b)", @strx), "string1", %if(%pos("(g)", @strx), etc...

"string1" is actually the name of a variable

I then do #ADDITEM @{@string1} mytext, which works, but also adds a @ at the beginning of the variable every time it makes a pass. After 5 passes I get something like:

@@@@@|The|quick|brown|fox|jumps

#SH @{@string1} works jsut fine, but #ADDITEM doesn't seem to be able to deal with it.

Many thanks :)

Posted: Tue Aug 13, 2002 9:17 pm

Sorry, I solved it - I took a nap and "Eureka!"

If the name of the variable was stored in another variable called TEST, then I only needed to do #ADDITEM @TEST blah

I feel silly