Best Practice?

[ChrisL]

What is the best practice when calling multiple functions that pass values around to each other.

Would you call each function and pass in the parameters?

Or set Global Variables and change them?

So

Func MyFirstFunc($var)
 ;Do stuff with $Var
         MySecondFunc($VAR)
Endfunc

Func MySecondFunc($iVar)

    Msgbox(0,"",$iVar)
EndFunc

Or

Global $iVar

Func MyFirstFunc()

 ;Do stuff with $iVar
     MySecondFunc()

Endfunc


Func MySecondFunc()

     Msgbox(0,"",$iVar)

Endfunc

The reason I ask is I have a script which is getting rather complicated passing information around, I was thinking of changing it to use Global values but I wanted to know if it's concidered bad practise

Edited May 27, 2009 by ChrisL

[dantay9]

I like passing on the parameters, but I guess it is a personal preference. Some people like to declare all variables at the beginning and use them throughout their script.

[Mat]

Global variables can get messy. fact.

MDiesel

[martin]

I like passing on the parameters, but I guess it is a personal preference. Some people like to declare all variables at the beginning and use them throughout their script.

It is a person preference but I think it is far better to avoid global variable because it's safer. For example take your example using a global variable

Global $iVar
 
 Func MyFirstFunc()
 
;Do stuff with $iVar
      MySecondFunc()
 Endfunc
 
 
 Func MySecondFunc()
 
      Msgbox(0,"",$iVar)
 
 Endfunc

It works fine. Then over a period of time you add code to both functions

Global $iVar
 
 Func MyFirstFunc()
   $Firstcal = function3($iVar)
;Do stuff with $iVar
      MySecondFunc()
  $secondcalc = function4($iVar);this might not give the expected result because $iVar has been changed by MySecondFunc.
 Endfunc
 
 
 Func MySecondFunc()
   
      Msgbox(0,"",$iVar)
     $iVar += 13
 Endfunc

Using Global variables makes maintaining or altering code a lot more difficult IMO, but it might make it easier to write in the first place.

But I do find it difficult to avoid using global variables, especially when I use OnEvent mode and functions used for GuiRegisterMessage.

Edited May 27, 2009 by martin

[ChrisL]

Cheers guys

martin you almost hit my problem on the head.

I have to keep adding to the functions, so what started out as passing 3 parameters is now up to 10

One of the functions is recursive so it passes the 10 paprameters back to the function when it finds a subfolder.

I'm going to re-write the functions and I was thinking shall I use Globals or keep passing parameters, after thinking about it I reakon I can simplify it without using Globals and out of the 3 replies that seems favorite.

Interesting point about onEvent, fortunately this script doesn't need a gui but I favour onEvent mode for gui's but I've never needed to pass in loads of parameters! (Yet)

[SmOke_N]

"Managed" Globals aren't necessarily a bad thing.

But I certainly (If could be avoided, and I haven't had a situation yet that it couldn't) would use parameters myself, keep the variables localized, and let them be discarded as need be.

[Juvigy]

I think the Best practice is using both methods. For example parameters that doesnt change - Globals. For frequently changing pars use parameter passing.

[ChrisL]

Thanks again

[Melba23]

ChrisL,

You mentioned you had up to 10 (expletive deleted!) parameters to pass. I used to use arrays when I had a lot of parameters to pass (only a mere 7 in the worst case) but I have now started using the Dictionary object method used by aGoriila's Hash.au3. Only one parameter to pass and you can use descriptive "keys" for each parameter rather than trying to remember which index number was what.

I recommend the UDF wholeheartedly - and as you can see it has a good pedigree! ;-)

M23