Zugg Software :: View topic - [1.30] Difficulty getting data records to work with local variables

Wizard Joined: 25 Mar 2003 Posts: 1113 Location: USA

I made an alias, similar to an alias I use often in zMUD, for adding values to data record variables more easily. With the recent change to local variables and how they work with #ADDITEM and #ADDKEY, I'm having problems getting the alias to behave the way I want. I know I could just scrap the alias and start all over with a different method of tracking, but I thought this post might help uncover situations where it's difficult or ambiguous as to how local variables work with some commands.

Posted: Thu Apr 26, 2007 6:32 pm

To use a local variable for indirect variable assignment, the syntax would be: @{$localvar}

The way indirect reference works is that you have @{whatever} and CMUD evaluates "whatever" as a string to produce the name of the variable. So, "whatever" can be any string expression, and using local variables should work. For example:

Posted: Thu Apr 26, 2007 6:38 pm

I have an alias that I use with the MXP send command that's this:

#alias vset($name,$val) {#var $name $value;#show $name is now <color %if($value,lime>ON,red>OFF)</color>}

And now, bizarrely, it doesn't set the variable right. If I were to do "vset test 1" the output is "1 is now ON", which is obviously wrong. If I remove the #var line, it works fine. Reckon the two are related?

Posted: Thu Apr 26, 2007 6:41 pm

I actually can't reproduce your issue Fang. Your example gives syntax errors when I try it on the command line.

Posted: Thu Apr 26, 2007 6:47 pm

When I typed it out, I typoed. The actual name of the second parameter is $value, not $val.

Posted: Thu Apr 26, 2007 6:56 pm

Right...even with that change I get errors about the > and < characters. I think you need some quotes somewhere.

Wizard Joined: 25 Mar 2003 Posts: 1113 Location: USA

My particular issue is with getting values into a non-local variable using the contents of a local variable (parameter with a name) as the variable name. The #ADDKEY command doesn't want the @ on the first parameter and using $var will treat $var as the variable to be assigned to rather than pull the value out and use that as a variable name. For now, I've re-written this alias using %1, %2, and %3 instead, but I'm still making use of local variables for some manipulation of the data. I just need to use %1 to assign the result back into a non-local variable.

I know there isn't really any way to "fix" the parser for a situation like this because it's not really a bug in the parser. It's just the way it has to address things, and I understand that my code needed to change.

Posted: Thu Apr 26, 2007 7:14 pm

How weird... it was working a few versions ago. It's compiling fine here, and even with quotes around the "lime>ON" and "red>OFF" parts, it's still producing the error. You could even just have

#alias test($name,$value) {#var $name $value;#show $name}

and the #show command shows whatever you typed as the second parameter. It's like the "#var $name $value" command is actually setting the value of the $name variable.

Wizard Joined: 11 Jul 2002 Posts: 1265 Location: USA

Have you tried?

#exec {"#ADDITEM "$var".keys {"%i"}"}

I think I used something similar to this before.

Posted: Fri Apr 27, 2007 7:29 pm

Fang, I tried your example and it seems to work fine here. When I type:

test var value

then it properly shows "value" on the screen. This is in a blank default session.

Arminas: that's why I recommended using %additem instead of #ADDITEM. It's always good to try and avoid using #exec when possible, since it can be slow. This should work:

#VAR @{$var} %additem(@{$var}, $key, %i)

Hmm, does this work. Maybe not...I'll have to think about it.

Larkin: You still shouldn't be using syntax like:

$keys = {%2}

why can't you just use

$keys = %2

Maybe you are using a work around for some old bug, but I'd hate to see people using the old sloppy syntax from zMUD.