[5.10B1] Procedure.i is no longer useful

[IceSoft]

I miss a new syntax check for returning a pointer of a structure from a function

This example is working but I use procedure.i (works also without adding the .i on the procedure key word)

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Structure myStructure
  a.i
  b.d
  c.s
EndStructure

Procedure.i test(*aa.myStructure)
  Debug "Procedure.i test(*aa.myStructure)"
  Debug *aa\a
  ProcedureReturn *aa
EndProcedure


a.myStructure 
a\a = 11
a\b = 44
a\c = "Test"

*b.myStructure = @a
Debug *b\a
Debug *b\b
Debug *b\c

*c.myStructure = test(*b)
Debug *c\a
Debug *c\b
Debug *c\c

Here an example for a structure pointer return value Syntax (Only an idea):

Procedure.<structure>* Functionname(Parameters)

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Procedure.myStructure* test1(*aa.myStructure)
  Debug "Procedure.myStructure test1(*aa.myStructure)"
  Debug *aa\a

  ProcedureReturn *aa
EndProcedure

[freak]

Is this a feature request? Where is the bug?

[IceSoft]

Is this a feature request? Where is the bug?

Bug or request? Make your own decission. It is not important how you declare this incomplete behavior of a purebasic syntax check;-)

I can returning a pointer of a structure. But I cannot declare the structure pointer as return value. That is it was I miss (not wish).

[Shield]

I can returning a pointer of a structure. But I cannot declare the structure pointer as return value. That is it was I miss.

That is simply because PB doesn't support this (unfortunately). The fact that you can return a structure pointer from an Integer procedure is because
PB does an implicit cast (unfortunately ), and it does that everywhere.

So no bug.

[IceSoft]

I can returning a pointer of a structure. But I cannot declare the structure pointer as return value. That is it was I miss.

That is simply because PB doesn't support this (unfortunately). The fact that you can return a structure pointer from an Integer procedure is because
PB does an implicit cast (unfortunately ), and it does that everywhere.

So no bug.

ok.

Please explain me this:
I get a syntax check error with 5.10 when I write:

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*a.i

correct is

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*a.Integer

Thats is ok but why get I no syntax error using

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Procedure.i 

but with this one i got an Syntax check error

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Procedure.Integer test()
 a.i
ProcedureReturn a
EndProcedure

and last but not least explain me the return value behavior of this but functions:

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Procedure testvalue()
  a.integer
  ProcedureReturn a
EndProcedure

Procedure.i testpointer()
  *a.integer
  ProcedureReturn *a
EndProcedure

Debug testvalue()
Debug testpointer()

[Demivec]

and last but not least explain me the return value behavior of this but functions:

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Procedure testvalue()
  a.integer
  ProcedureReturn a
EndProcedure

Procedure.i testpointer()
  *a.integer
  ProcedureReturn *a
EndProcedure

Debug testvalue()
Debug testpointer()

I'll comment the above code to explain the values:

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Procedure testvalue()
  a.integer
  ;When the structure is used without a field it returns the address of the structure.
  ;To return the value of a structure field use the field (i.e. a\i)
  ProcedureReturn a
EndProcedure

Procedure.i testpointer()
  *a.integer
  ProcedureReturn *a ;returns the value of the pointer, which is zero since it has not been assigned any other value since being declared
EndProcedure

Debug testvalue()
Debug testpointer()

[Shield]

Please explain me this:
I get a syntax check error with 5.10 when I write:

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*a.i

correct is

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*a.Integer

Thats is ok...

Right, because typed pointers don't make sense, it only makes sense if the type refers to the target memory.

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Procedure.i 

but with this one i got an Syntax check error

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Procedure.Integer test()
 a.i
ProcedureReturn a
EndProcedure

Yes, because Integer is not the same as ".i". Integer is a structured type, not a plain data type.

and last but not least explain me the return value behavior of this but functions:

Code: Select all

Procedure testvalue()
  a.integer
  ProcedureReturn a
EndProcedure

Procedure.i testpointer()
  *a.integer
  ProcedureReturn *a
EndProcedure

Debug testvalue()
Debug testpointer()

The first procedure returns the address of the structured variable 'a'. Because that variable is placed on the stack,
it will be dropped after returning from the procedure, i.e. the pointer is useless because the variable doesn't exist anymore.
If you write ProcedureReturn a\i you will get the actual "plain data" value.

The second procedure returns a pointer to an Integer structure.
If you use allocate memory inside the procedure you can create a memory block which is still valid after
returning from the procedure. Since PB uses implicit type casting, it will cast the address to an integer
which is technically the same (since both are regular integer values of the same size).


I said it's no bug...that doesn't mean I don't agree on sometimes inconsistent syntax and missing features
which are essential in my opinion.