Dynamically create Globals

[bobh]

I have an application where I dynamically create variables based on key/values read from a downloaded INI file. The keyname becomes the variable name and the key value becomes the variable value. I use the "Assign" command to do this. This works fine except that the variable name must be pre-defined in a "Global" statement at the beginning of the program. This means that every variable I "might create" from the file INI must be predefined in the Autoit script. If I want to create new variables based on the data in INI file, I have to recompile the program to set the Global statements.

Is there some way to dynamically declare global variables without having to recompile the program?? For example, could I read a list of variable names from a file (or an INI section) and define them globally before I actually start processing the rest of the INI file??

Thanks.

[DW1]

Check out the third parameter in Assign()

[optional] controls the way that variables are assigned (add required options together):
0 = (default) Create variable if required
1 = Force creation in local scope
2 = Force creation in global scope
4 = Fail if variable does not already exist

[Edano]

Assign ( "varname", "data" [, flag] )

Parameters varname The name of the variable you wish to assign. Cannot be an array element. data The data you wish to assign to the variable. flag [optional] controls the way that variables are assigned (add required options together):

0 = (default) Create variable if required

1 = Force creation in local scope

2 = Force creation in global scope

4 = Fail if variable does not already exist

[bobh]

Thanks for the responses. Unfortunately, the flag value on Assign does not seem to work for me. In the following, when the Global is commented out, the MsgBox will give "ERROR: $bob: undeclared global variable." when I try to run the test script. If I uncomment the Global statement, the MsgBox displays "hi".

;Global $bob

Assign('bob','hi',2)

MsgBox(0,'',$bob)

[guinness]

Assign should be used with Eval, therefore look at using Eval OR just declare the variable as normal.

[bobh]

Could you give me an example of how you would use EVAL with ASSIGN? I thought I've tried most combinations of EVAL already.

The whole purpose of my original post was to find a way to avoid declaring some of my variables in the normal way.

Thanks

[guinness]

Help file is your first port of call.

[Edano]

this does work:

.

_Main()

MsgBox(0,"",$t)

Func _Main()

    Assign("t",12,2)

EndFunc

.

E

[Edano]

another question is: why do you need the variable names from the ini ? you can hardly work with them within the script.

Edited August 1, 2013 by Edano

[Edano]

Thanks for the responses. Unfortunately, the flag value on Assign does not seem to work for me. In the following, when the Global is commented out, the MsgBox will give "ERROR: $bob: undeclared global variable." when I try to run the test script. If I uncomment the Global statement, the MsgBox displays "hi".

;Global $bob

Assign('bob','hi',2)

MsgBox(0,'',$bob)

.

btw, this works for me as well

[kylomas]

The whole purpose of my original post was to find a way to avoid declaring some of my variables in the normal way.

 

If you don't mind, why?  This makes troubleshooting very difficult.  What is the advantage of using dynamically declared variables?

kylomas

Edited August 1, 2013 by kylomas

[Edano]

you could save keys and values in an array and work with that instead. would be cleverer

Edited August 1, 2013 by Edano

[bobh]

As a test,  tried the snippet from Edano:

_Main()

 

MsgBox(0,"",$t)

 

Func _Main()    

   Assign("t",12,2)

EndFunc

 

This fails for me on my workstation the same way as my code, i.e. "ERROR: $t: undeclared global variable". If this works for someone else and fails for me, I'm thinking there must be a difference in my install. I'm running the latest production version of Autoit and the 3.3.0 version of SciTe. To my knowledge I haven't made any changes to property files that would control how scripts compile.

 

Curious!

[DW1]

 

As a test,  tried the snippet from Edano:

_Main()

 

MsgBox(0,"",$t)

 

Func _Main()    

   Assign("t",12,2)

EndFunc

 

This fails for me on my workstation the same way as my code, i.e. "ERROR: $t: undeclared global variable". If this works for someone else and fails for me, I'm thinking there must be a difference in my install. I'm running the latest production version of Autoit and the 3.3.0 version of SciTe. To my knowledge I haven't made any changes to property files that would control how scripts compile.

 

Curious!

 

 

Not really curious at all, as pointed out by guinness, assign() should be used with eval().

Assign should be used with Eval, therefore look at using Eval OR just declare the variable as normal.

 

_Main()

MsgBox(0,"",Eval("t"))

Func _Main()
   Assign("t",12,2)
EndFunc

 

That being said, I still don't see a reason to complicate things with dynamic variable names.  Keys and Values stored in an array, as already suggested would be a much better solution.

[guinness]

I can't understand why you're overcomplicating this. Can you demonstrate the benefit of what you're to do?

[TheSaint]

I can guess that he probably doesn't know beforehand, the keys and values that will be in the ini files?

That said, I agree that he appears to be making this overly complex.

My personal view in these matters, is to refrain from giving any help, until the questioner provides some code and a greater understanding to go by. It can really save on a lot of unnecessary stuff ... and we shouldn't really have to be the ones fishing.

@bobh - We (trancexx excepted at her request) help those who help themselves.

[guinness]

I think an associative array is what he is after.

[Edano]

 

As a test,  tried the snippet from Edano:

_Main()

 

MsgBox(0,"",$t)

 

Func _Main()    

   Assign("t",12,2)

EndFunc

 

This fails for me on my workstation the same way as my code, i.e. "ERROR: $t: undeclared global variable". If this works for someone else and fails for me, I'm thinking there must be a difference in my install. I'm running the latest production version of Autoit and the 3.3.0 version of SciTe. To my knowledge I haven't made any changes to property files that would control how scripts compile.

 

Curious!

.

the codes are correct. this is a problem with au3 check. when you run the snippet without au3 check, there is no error. au3 check does obviously not understand assign(). i noted that before, but nobody listens. instead they will beat me now again and tell me that i understand nothing. you will see.

eval has nothing to do with it.

E.

[guinness]

From the help file....

 

Remarks If there is a need to use Assign() to create/write to a variable, then in most situations, Eval() should be used to read the variable and IsDeclared() should be used to check that the variable exists.

[BrewManNH]

.

the codes are correct. this is a problem with au3 check. when you run the snippet without au3 check, there is no error. au3 check does obviously not understand assign(). i noted that before, but nobody listens. instead they will beat me now again and tell me that i understand nothing. you will see.

eval has nothing to do with it.

E.

Au3Check understands Assign, it just doesn't understand what is being assigned, and there's a lot of times that it would be impossible for it to understand what is being assigned to what. As an example...

For $I = 1 to 10
    Assign("Dog" & $I, 12 + $I)
Next

If you were to try and refer to the variable $Dog3, au3check would throw an undeclared variable error, because it can't know what "Dog" & $i equals at runtime. Obviously, AutoIt will understand what $Dog3 is because you've assigned it previously. It's the same logic as (for example) FileInstall and using anything other than a literal path and/or filename on the left side of the function, because at compile time the variable doesn't mean anything to the compiler.