Storing UDT's in Hash

[simon]

Hi

My name is Simon. I'm new to this forum. I'm 48 years old now and used GFA-BASIC alot during the late 80's and early 90's on AMIGA. I have been downloading GFA-BASIC 32 from Sjouke Hamstra again and again to play a little with it. But otherwise I acutally use PowerBasic. I think he is doing a great job in preserving this wonderful language and keeping it up to date.

I was looking for a solution to store UDT's in a Hash, which GB cannot do intrinsically. I tried to overcome this by storing a UDT into a String and then storing that one in a Hash. By now this approach seems to work. Anyone ever tried, also? Or any other ideas?


$Library "gfawinx"
$Library "UpdateRT"
UpdateRuntime      ' Patches GfaWin23.Ocx


Global daten As Hash String

Type myType
 nm As String*20
 dat As Int
EndType

Global MYTYPE_SIZE As Int = SizeOf(myType)


Main:
InitData
PrintHash
End

Procedure InitData
 Local d1 As myType, d2 As myType, d3 As myType

 d1.nm = "Simon" : d1.dat = 100
 d2.nm = "Hansi" : d2.dat = 200
 d3.nm = "Sarah" : d3.dat = 300

 daten["eins"] = StrPeek(V:d1, MYTYPE_SIZE)
 daten["zwei"] = StrPeek(V:d2, MYTYPE_SIZE)
 daten["drei"] = StrPeek(V:d3, MYTYPE_SIZE)
EndProcedure

Procedure PrintHash
 Local s$
 Local temp As myType

 For Each s$ In daten[]
   MemMove V:temp, V:s$, MYTYPE_SIZE
   Trace temp.nm
   Trace temp.dat
 Next
EndProcedure



[(X)]

Hi Simon,

Your code seems to check out:

TRACE:PrintHash(1):temp.nm = Simon
TRACE:PrintHash(2):temp.dat = 100
TRACE:PrintHash(1):temp.nm = Hansi
TRACE:PrintHash(2):temp.dat = 200
TRACE:PrintHash(1):temp.nm = Sarah
TRACE:PrintHash(2):temp.dat = 300

[dragonjim]

Hi Simon,

Yes, I used a similar approach some years ago using memory blocks - essentially the same as using custom fixed length strings. The only difference is I stored the memory block address in the Hash instead of the String. Your approach is probably better as it is more stable.

Well done and welcome to the forum.

[dragonjim]

...one possible improvement to your code would be to store the UDT in an array; this would allow you to use functions to store and retrieve data.

I'm not near a computer right now, but I will post some examples of what I mean when I am.

[(X)]

Here's a clue: If you execute:

Trace <some_UDT>

GB32 automatically lists the contents of the UDT in the Debug Output window.
This implies that GB32 can peer into a user data structure.

Perhaps this can be leveraged to store all the properties/members of a UDT into a Hash automatically while preserving the property names.

$Library "gfawinx"
$Library "UpdateRT"
UpdateRuntime      ' Patches GfaWin23.Ocx

Type myType
 nm As String*20
 dat As Int
EndType
Dim mt As myType

Trace mt

Debug Output Window:

TRACE:(1):mt =
.nm =
.dat = 0

[(X)]

This shows some built-in features related to UDTs.

Debug "- Did you perform a syntax check first? (Shift+F5)"

' Sample
Type RECT
 - Int32 left, top, right, bottom
EndType

Type test
 tstl(6 .. 7) As Long
 tsts As String*20
 rc(2) As RECT
EndType

Form frm1
Trace frm1

Debug.Show

Dim udt As Gfa_Type, i%
For Each udt In Gfa_Types
 Try
   Debug "Type ";udt.Name(0)
   For i = 1 To udt.Count
     Debug "  ";udt.Name(i);
     If udt.IsArray(i) Then
       Debug "(";udt.LBound(i);"..";udt.UBound(i);")";
     EndIf
     Debug " As ";udt.TypeName(i);#9;" // Type: ";udt.Type(i)
   Next
   Debug "EndType"
 Catch
   Debug "Error in Print_type ";Err;Err$
 EndCatch
Next

Do
 Sleep
Until frm1 Is Nothing
Debug:

- Did you perform a syntax check first? (Shift+F5)
TRACE:(1):frm1 = Object(Form(frm1):0x24517f0)
Type RECT
  left As Integer // Type: 3
  top As Integer // Type: 3
  right As Integer // Type: 3
  bottom As Integer // Type: 3
EndType
Type test
  tstl( 6.. 7) As Integer // Type: 3
  tsts As String * 20 // Type: 8
  rc( 0.. 2) As RECT // Type: 65536
EndType

[simon]

Wow. Thats amazing! Not to mention that it'll take a moment for me to understand what you did. But definitly a direction to explore.