[Implemented] CopyStructure()

[Froggerprogger]

Hi once again!

Forget about my above solution, it's too complicated and not various enough.

Here's a way from 'NicTheQuick' from the German board:

Code: Select all

Structure Strukt 
  Byte.b 
  Word.w 
  Long1.l 
  Long2.l 
  String1.s 
  Float.f 
  String2.s 
EndStructure 
Global Struc_Strukt.s 
Struc_Strukt = "bwllsfs" ; This structure's types in a string

Structure AllTypes 
  StructureUnion 
    b.b 
    w.w 
    l.l 
    f.f 
    s.s 
  EndStructureUnion 
EndStructure 

Procedure CopyStructure(*Var1.AllTypes, *Var2.AllTypes, *Struc.BYTE) 
  Protected Length.l 
  
  While *Struc\b 
    Select *Struc\b 
      Case 'b' : *Var2\b = *Var1\b : *Var1 + 1 : *Var2 + 1 
      Case 'w' : *Var2\w = *Var1\w : *Var1 + 2 : *Var2 + 2 
      Case 'l' : *Var2\l = *Var2\l : *Var1 + 4 : *Var2 + 4 
      Case 'f' : *Var2\f = *Var1\f : *Var1 + 4 : *Var2 + 4 
      Case 's' : *Var2\s = *Var1\s : *Var1 + 4 : *Var2 + 4 
    EndSelect 
    *Struc + 1 
  Wend 
EndProcedure 

Similar to this a PB-built-in CopyStructure could work:

CopyStructure(*struct1.myStructX, flags, [*struct2.myStructY])

When flags are 0 then only the memory is copied similar to CopyMemory.
With flag "#PB_CopyStrings" set, PB looks at compile-time into the structure-definition of the structure (needn't be the same for both - if the optional aim is given just ignore it's structure) and duplicates all strings (even those of contained structures - which is no problem also).
If no optional aim is given return pointer to a new copy of *struct1.


Of course this wouldn't work for WinApi-Structures containing stringpointers declared as '.l', but who cares about that as long as it works for all strings declared as '.s' ?

[ROUMANET]

I didn't realize until just now that there is no way to copy a structure (with it's data)..

It'd be nice to have a CopyStructure() and some way to compare whole structures (and the data within).

I would the same thing + WriteStructureFile() and ReadStructureFile() like in Rapidq Basic

Golfy

[Shannara]

Hmm, but remember, the more strings you have in your structures the faster your memory willl leak Hopefully fred has this fixed in the next version of PB along with the network memory leak.

[newbie]

I didn't read carefully all your posts, but in a program I have done, I was storing strings into structures like this :

Code: Select all

Structure mystruct
    var1.b[20]
    var2.b[50]
    var3.l
EndStructure

struct.mystruct

string.s = "mystring here"
PokeS(@struct\var1[0], string)
string = "another text"
PokeS(@struct\var2[0], string)
struct\var3 = 99

Debug "struct before copymemory"
Debug "struct\var1[0] = " + PeekS(@struct\var1[0])
Debug "struct\var2[0] = " + PeekS(@struct\var2[0])
Debug "struct\var3 = " + Str(struct\var3)
Debug " "

anotherstruct.mystruct

CopyMemory(@struct, @anotherstruct, SizeOf(mystruct))

string = "toto"
PokeS(@struct\var1[0], string)
PokeS(@struct\var2[0], string)
struct\var3 = 32

Debug "struct modified purposefully after copymemory :"
Debug "struct\var1[0] = " + PeekS(@struct\var1[0])
Debug "struct\var2[0] = " + PeekS(@struct\var2[0])
Debug "struct\var3 = "    + Str(struct\var3)
Debug " "

Debug "anotherstruct after copymemory (not altered): "
Debug "anotherstruct\var1[0] = " + PeekS(@anotherstruct\var1[0])
Debug "anotherstruct\var2[0] = " + PeekS(@anotherstruct\var2[0])
Debug "anotherstruct\var3 = "    + Str(anotherstruct\var3)

Actually this seems to work.

[Froggerprogger]

@newbie
Yes, but than you are limited to a fixed string-size.
And you always do have to use PokeS (and PeekS to use the string-functions, because there are no Stringpointers e.g. *bla.s = @struct\var1[0]).

[newbie]

I am not limited, I just size my structure with the max size of the string (e.g 256 for a file name).
The pb is that you waste few bytes (those unused) and that a dedicated CopyStructure would allow us to declare string instead of bytes, but as I said,
it works, take it as a workaround