PureBasic Forums - English

Posted: **Fri May 14, 2021 3:55 pm**

Structure t1
  l.l
  a.a
EndStructure
Structure t2
  d.d
  b.t1
EndStructure

a.t2
Debug SizeOf(a)
Debug SizeOf(a\b)
Debug SizeOf(a\b\a) ; <- Syntax error?!

Debug SizeOf(t2)
Debug SizeOf(t2\b)
Debug SizeOf(t2\b\a); <- dito

Posted: **Fri May 14, 2021 10:49 pm**

Would you call it a bug? I would say it is a missing feature.
From the documentation it is not clear, if SizeOf also allows nested structure calls insteat of just the field of the present structure.

A similar "missing feature" is the OffsetOf() of nested structures.
Here you need an addition:

Code: Select all

Debug OffsetOf(t2\b) + OffsetOf(t1\a)   ; Debug OffsetOf(t2\b\a)

Posted: **Sat May 15, 2021 8:32 am**

the problem is, i used it at the moment to identify a structure dynamicaly.

Code: Select all

Structure ab
  StructureUnion;structure-union is the trick here 
    _type.b[1]
    somedata.l
  EndStructureUnion
EndStructure

Structure bc
  StructureUnion
    _type.b[2]
    elsedata.l
  EndStructureUnion
EndStructure

Procedure ab_doit(*a.ab)
  Debug "AB-Variant"
EndProcedure

Procedure bc_doit(*b.bc)
  Debug "BC-Variant"
EndProcedure

Macro GetType(x): SizeOf(x\_type) :EndMacro

Macro doit(x)
  CompilerSelect GetType(x)
    CompilerCase gettype(ab)
      ab_doit(x)
    CompilerCase gettype(bc)
      bc_doit(y)
    CompilerDefault
      CompilerError "[doit] Supported type"
  CompilerEndSelect
EndMacro

Define var.ab, ok.bc

doit(var)
doit(ok)

The good thing with this method is, that it is done on compiler-level without any additional code or memory used. Very Usefull, when you work with matrix and vectors...

As long as you don't use nested structures everything works perfectly.

Posted: **Sun May 14, 2023 8:48 pm**

Yes please, allow nested structures for SizeOf(), the C of the arduino does allow it.

I know, it might be hard but very useful at the end.
Another fast example:

Code: Select all

structure pepe
  jose.f
  juan.d
endstructure
Structure Person
  Name.s
  ForName.s 
  Age.pepe
EndStructure
var.person
Debug sizeof(person\Age); <- if this is allowed ...
;Debug sizeof(person\Age\juan); <- why this one is not?. At least it is not a "Syntax error" !

PureBasic Forums - English

SizeOf and nested structures

SizeOf and nested structures

Re: SizeOf and nested structures

Re: SizeOf and nested structures

Re: SizeOf and nested structures