SRL Archive - OSR Outdated Tutorials

I've noticed a lot of our beginner scriptwriters here haven't noticed that types have sizes or how to get these sizes.

I wrote a small example script to show sizes and what they mean for the people who just wanna get to it and not read, It can be found neer the end.


You can get the size in bytes for a type doing the following. SizeOf(V);

var
  B: byte;
begin
  WriteLn(SizeOf(B)); //1
end.

You can get the maximum of a unsigned variable doing the following. Pow(2, SizeOf(V) * 8) - 1;

var
  B: byte;
begin
  WriteLn(Pow(2, SizeOf(B) * 8) - 1); //255
end.

You can get the maximum of a signed variable doing the following. (Pow(2, SizeOf(V) * 8) - 2) / 2;
Note: Add 1 and negate for Minimum.

var
  B: byte;
begin
  WriteLn((Pow(2, SizeOf(B) * 8) - 2) / 2); //127
end.

Byte
Size: 1 byte
Range: 0..255

ShortInt
Size: 1 byte
Range: -128..127

Word
Size: 2 bytes
Range: 0..65535

SmallInt
Size: 2 bytes
Range: -32768..32767

Cardinal (AKA LongWord)
Size: 4 bytes
Range: 0..4294967295

Integer
Size: 4 bytes
Range: -2147483648..2147483647


This next ones are not that important but ill include them =)

Single
Size: 4 bytes
Range: 1.5x10**-45..3.4x10**38

Double
Size: 8 bytes
Range: 5.0x10**-324..1.7x10**308

Extended
Size: 10 bytes
Range: 3.6x10**-4951..1.1x10**4932

program _;

function PadC(s: string; maxl: integer): string;
begin
  Result := s;
  while (Length(Result) < maxl) do
  begin
    Result := ' ' + Result + ' ';
    if (Length(Result) = maxl - 1) then
      Result := ' ' + Result;
  end;
end;

function DebugType(Name: string; Size: integer; Unsigned: boolean): string;
var
  MaxS: Extended;
begin
  Result := '|' + PadC(Name, 12) + '|';

  if (Size > 1) then
    Result := Result + PadC(IntToStr(Size) + ' bytes', 10) + '|'
  else
    Result := Result + PadC(IntToStr(Size) + ' byte', 10) + '|';

  MaxS := Pow(2, Size * 8) - 1;
  if (not (Unsigned)) then
  begin
    MaxS := (MaxS - 1) / 2;
    Result := Result + PadC('-' + FloatToStr(MaxS + 1) + '..' + FloatToStr(MaxS), 27) + '|';
  end else
    Result := Result + PadC('0..' + FloatToStr(MaxS), 27) + '|';
end;

var
  B: Byte;
  SI: ShortInt;
  W: Word;
  SmI: SmallInt;
  C: Cardinal;
  I: Integer;

begin
  WriteLn('|    Type    |   Size   |            Range          |');
  WriteLn(DebugType('Byte', SizeOf(B), True));
  WriteLn(DebugType('ShortInt', SizeOf(SI), False));
  WriteLn(DebugType('Word', SizeOf(W), True));
  WriteLn(DebugType('SmallInt', SizeOf(SmI), False));
  WriteLn(DebugType('Cardinal', SizeOf(C), True));
  WriteLn(DebugType('Integer', SizeOf(I), False));
end.

Small Note: The script uses to function that asks for "Unsigned", first if a number is signed, 1 bit is taken and the number can be negative or positive. If its Unsigned the number goes from 0 to its maximum. As you can see above Byte and ShortInt have the same Size but diffrent Ranges, this is because Byte is unsigned.

This is very helpful actually.
Would you add in the sizes for integer, string (I'm sure there gonna be a character limit)

Is char even supported?

From: HarryJames
This is very helpful actually.
Would you add in the sizes for integer, string (I'm sure there gonna be a character limit)

Is char even supported?

Char = ShortInt;
Integer is already there.
String is basically an array of char so its only limited by memory.

Thanks for char/string.
I didn't see integer - I'm on my iPod and very tired. I've got a full day of sixthform to start in an hour :(

From: HarryJames
Thanks for char/string.
I didn't see integer - I'm on my iPod and very tired. I've got a full day of sixthform to start in an hour :(

It's there, but here,

Integer
Size: 4 bytes
Range: -2147483648..2147483647

I never knew we even had sizeof(), not that I would have ever used it…interesting though.

;) I assume you were inspired by C? :)

Also, I had no idea PascalScript had a SizeOf operator. I assume it's actually a function and not a unary operator like in C though.

Reminds me that there's not a whole lot of information about why things work, rather than how to make them work. Makes me sad. :/

Rep++.

From: i luffs yeww
;) I assume you were inspired by C? :)

Also, I had no idea PascalScript had a SizeOf operator. I assume it's actually a function and not a unary operator like in C though.

Reminds me that there's not a whole lot of information about why things work, rather than how to make them work. Makes me sad. :/

Rep++.

Noticed it when doing some C->Pascal work and playing with the Windows API in Simba =)

I've known about SizeOf for a long time tho I never knew what unsigned meant until learning C.

C -> Pascal? Windows API? D: For what/why?

Anyway, does Pascal have unsigned types? More importantly, does PascalScript?

From: i luffs yeww
C -> Pascal? Windows API? D: For what/why?

Anyway, does Pascal have unsigned types? More importantly, does PascalScript?

Yes but you cant like specify var name: unsigned integer; there named differently like a Cardinal is a unsigned integer.

BTW been playing with the Windows API can can now move the mouse and get mouse position in C. (Tho only in windows)

All you have to do is #include <windows.h> isn't it? :p

Anyway, not on the right thread for this discussion imo.

SizeOf() Also works on custom types

type
  TItem = record
    Name      : string;
    StatsName : string;
    UpText    : TStringArray;
    InvSlot   : Integer;
    Stackable : Boolean;
    EquipLevel: Integer;
    DTM       : Integer;
  end;

var
  B : TItem;

begin
  WriteLn(SizeOf(B));
end.

From: Zyt3x
SizeOf() Also works on custom types

Well that makes sense, since custom types are just normal types, really. What would the size of that be, though? Not sure what size uninitialized strings and TStringArrays would be, so I really have no idea. I was guessing 16 (which would make strings and TStringArrays one byte?), but I don't know.

Quite an interesting read, thanks