Support pointer (structure) as return value in procedures

[IceSoft]

@Fred,
Please support Structure-Pointer as return value (see example it work but I have to declare the procedure return value as Integer)
Maybe adapting the syntaxcheck and find a nice syntax (e.g.: Procedure.aStr* or Procedure.*aStr) and it more easier to write wrappers for PureBasic.

Thanks.

Code: Select all

Structure aStr
  b.l
  a.i
EndStructure

; Procedure.aStr* test()       <<<<<<<<<<<<<<<<<<   Compiler syntax error
;   ddd.aStr
;   ddd\a = 100
;   ddd\b = 10
;   ProcedureReturn @ddd
; EndProcedure


Procedure.i test()
  Static ddd.aStr
  ddd\a = 100
  ddd\b = 10
  ProcedureReturn @ddd
EndProcedure

*bb.aStr = test()

Debug *bb\b
Debug *bb\a

[helpy]

It will also work (and it is allowed!!!) if you write:

Code: Select all

Procedure test()
  ....
EndProcedure

You do not have to give .i as return type!
.i is the default return type if you write nothing!

cu,
guido

[IceSoft]

It will also work (and it is allowed!!!) if you write:

Code: Select all

Procedure test()
  ....
EndProcedure

You do not have to give .i as return type!
.i is the default return type if you write nothing!
cu,
guido

´
If you think this is ok?
If yes than we should have only one type for all

[Thorium]

If you think this is ok?
If yes than we should have only one type for all

You cant have one type for all.
All that is the size of Integer or less will be return in EAX register. So there is no difference in returing .i or .b. But if the datatype is bigger like quad on x86 the compiler need to take special care of that.

[IceSoft]

Thorium,
You should read about the: var (C#-Referenz)

The .i is not wrong but bad.
If I want to create automatic online help file from a wrapper for PureBasic I have to adapt the return parameter info. That is not really usefull.

[Mistrel]

So there is no difference in returing .i or .b.

How can you fit a 32/64-bit pointer into an 8-bit byte?

It will just wrap around.

[Thorium]

So there is no difference in returing .i or .b.

How can you fit a 32/64-bit pointer into an 8-bit byte?

It will just wrap around.

Forget what i wrote, it's wrong. ^^

I meant there is no difference in speed and memory usage. As it will be returned in EAX/RAX, no matter if it's .i or .b.

[PMV]

Please support Structure-Pointer as return value (see example it work but I have to declare the procedure return value as Integer)
Maybe adapting the syntaxcheck and find a nice syntax (e.g.: Procedure.aStr* or Procedure.*aStr) and it more easier to write wrappers for PureBasic.

You should try a OOP-Language.

PB does only return a 32-Bit (or 64-Bit) value. PB does not know
what structure is behind the pointer. If you want such functionality,
there are a lot of OOP-Languages available.
You could wish a Pointer-Type .p to define, that you want to return
a pointer, not only a value. But for me, it would also be to OOP-like


btw.:

A procedure can return a value or a string if necessary. You have to set the type after Procedure and use the ProcedureReturn keyword at any moment inside the procedure. A call of ProcedureReturn exits immediately the procedure, even when its called inside a loop.

MFG PMV

[IceSoft]

I dont want realy a functionality.
I want only a more friendly PureBasic compiler:
1. New Keyword for pointers (not i) => better: Procedure.*<type>
2. Compiler substituite: Procedure.*<type> with this one: Procedure.i intern
3. No compiler warning it I use Procedure.*<type>

Thats all and it improve the reading of PureBasic source code too.

[PMV]

So, you only want to write this, because your code looks better?
What do you think about this?

Code: Select all

Macro p
  i
EndMacro

Structure aStr
  b.l
  a.i
EndStructure

Procedure.p test()      
  ddd.aStr
  ddd\a = 100
  ddd\b = 10
  ProcedureReturn @ddd
EndProcedure

*bb.aStr = test()

Debug *bb\b
Debug *bb\a

The star isn't allowed, but you could wish to be allowed in
macros or structurenames

MFG PMV

[IceSoft]

SoThe star isn't allowed, but you could wish to be allowed in
macros or structurenames

Only with <= PB 4.51.

It is better we need no macro on this place.

[Thorium]

Well the point of a pointer is that it's not fixed to a structure. You can let it point to what ever structure you want. So defining the return value as a structure would be wrong. And i dont think it looks much better. If you want to keep track about what structures the pointer can point to, just place a comment in front of the procedure. Thats what i do.

[freak]

We're not adding compiler features just for cosmetics. If you want your code to look different, just use macros. That's what they are for.

[IceSoft]

Is is not for cosmetic. Never!
It is a feature which improve the compiler...if you make a type check:

Code: Select all

ProcedureReturn.i foo1()
  tt.aStruc1
    ....
  ProcedureReturn @tt.aStruc1
EndProcedure
 ProcedureReturn.aStruc1 foo2()
  tt.aStruc1 
    ....
  ProcedureReturn @tt.aStruc1
EndProcedure

*b.Struc1 = foo1()
*c.Struc2 = foo2()   <<< Compiler can make a warning (*variable.Struc2 <> *RetrunValue.Struc1)

*i is more a void pointer

[Thorium]

Why should it output a warning? It's legal to return the pointer, even if it poits to another structure.
Btw. your code does not work because you are using fixed structures. They do not exist any longer after the procedure is terminated. You need to use pointers and allocate memory for the structures.