PureBasic Forums - English

Posted: **Fri May 19, 2006 1:36 pm**

Like in C, it could be useful in some case to 'undef' a variable.

for example, the NOTIFYICONDATA structure is declared in PureBasic but it is the Win95 definition.
If i want to define my own WinXP compatible structure i have to rename it as something like NOTIFYICONDATA_XP.

so, in this case, an UnDefine keyword could be use as this :

Code: Select all

CompilerIf Defined(NOTIFYICONDATA, #PB_Structure) ; Compiler check not really useful
  
  UnDefine NOTIFYICONDATA ; Undefine the Win95 definition
  
  Structure NOTIFYICONDATA ; Updated for WinXP
    cbSize.l
    hwnd.l 
    uId.l 
    uFlags.l 
    uCallbackMessage.l 
    hIcon.l 
    szTip.c[64]
    dwState.l
    dwStateMask.l 
    szInfo.c[256] 
    StructureUnion 
      uTimeout.l 
      uVersion.l 
    EndStructureUnion 
    szInfoTitle.c[64]
    dwInfoFlags.l
    guid.GUID
  EndStructure 
  
CompilerEndIf

Posted: **Fri May 19, 2006 4:09 pm**

I disagree because I think every structure with the same name should be the same. It's a bit having two local variables with the same name but different types - it becomes messy.

Posted: **Fri May 19, 2006 6:05 pm**

I think every structure with the same name should be the same

i'm speaking about the possibility to redefine purebasic built-in constants/structs/...
For example, in the MSDN which i often need/read, when a structure is updated it always keep the same name. MS structures are backward compatibles.

it becomes messy.

Yes, but it is powerful !

And if you do not call 'Undefine' you can't make side-effect errors.
When it's needed (rarely) it's cool to have.

:roll:

Posted: **Fri May 19, 2006 7:04 pm**

If the PB version of a structure is not correct or outdated just report it to Fred and I'm sure he'll change it.

Posted: **Fri May 19, 2006 9:11 pm**

THat'll take some time and then when Fred releases the next version of PB that takes just another week... I think Flype's idea takes 2 seconds

Posted: **Fri May 19, 2006 9:44 pm**

Trond wrote:If the PB version of a structure is not correct or outdated just report it to Fred and I'm sure he'll change it.

yes kindy fred always do.

but well it's just an idea, not very important.
that might be useful.

PureBasic Forums - English

UnDefine array/const/interface/list/struct/var

UnDefine array/const/interface/list/struct/var