Global variables inside Procedures

VB6_to_PBx · **Joined:** Mon May 09, 2011 9:36 am **Posts:** 522

is it OK to place Global variables inside Procedures ?

some of these same Global variables would then be accessed in other Procedures in my Program .

anyone see potential problems with doing this ?

skywalk · **Posted:** Fri Aug 23, 2019 10:09 pm

Why not?
I put many def's in Main() or Init().

spikey · **Posted:** Fri Aug 23, 2019 10:27 pm

You should be aware that there is the potential to create accidentally a scope ambiguity bug:-

Code:

Procedure P1()
  
  V = 1
  
  Debug V
  
EndProcedure

Procedure P2()
  
  Global V.I 
  
  Debug V
  
EndProcedure

P1()
P2()

Debug V

If you run this code you will get the output:-

Code:

1
0
0

The variable V isn't truly global despite appearing to be. P1 will implicitly create a local variable, which will be inaccessible to other procedures.

(Putting EnableExplict at the top of your code will detect this error, but if your code isn't currently written to allow that you'd need a refactor).

Little John · **Posted:** Fri Aug 23, 2019 10:54 pm

viewtopic.php?f=13&t=54221

VB6_to_PBx · **Joined:** Mon May 09, 2011 9:36 am **Posts:** 522

Little John wrote:

https://www.purebasic.fr/english/viewtopic.php?f=13&t=54221

from Fred :

Quote:

Global is OK in procedures

i'm doing something like this ... i call the 1st Procedure which holds the Global variables
then call the other Procedures that calculate data

Code:

EnableExplicit 

Procedure SetGlobalVar()
  Global var=1
EndProcedure

Procedure ShowGlobalVar()
  Debug var
EndProcedure


SetGlobalVar()
ShowGlobalVar()

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