Talking about dynamic arrays I was just curious if we could us the new
management operators to make dynamic arrays that are managed on the stack.
Here’s a quick demo I typed up but I don’t understand why the init/dealloc
count isn’t balanced. Calling the constructor seems to be the culprit, but why?
type
generic TDynArray<T> = record
private type TDynArrayTable = array[0..0] of T;
private type TDynArrayTablePtr = ^TDynArrayTable;
private
table: TDynArrayTablePtr;
public
constructor Create (values: array of T);
procedure Push(value: T);
class operator Finalize(var a: TDynArray);
class operator Initialize(var a: TDynArray);
end;
constructor TDynArray.Create (values: array of T);
var
value: T;
begin
for value in values do
Push(value);
end;
class operator TDynArray.Initialize(var a: TDynArray);
begin
writeln('init');
a.table := nil;
end;
class operator TDynArray.Finalize(var a: TDynArray);
begin
FreeMem(a.table);
a.table := nil;
writeln('dealloc');
end;
procedure TDynArray.Push(value: T);
begin
if table = nil then
table := GetMem(0);
writeln('push ', value); // grow array etc...
end;
procedure TestDynArray;
type
TIntArray = specialize TDynArray<Integer>;
var
d: TIntArray;
begin
d := TIntArray.Create([1, 2, 3]);
d.Push(100);
end;
========
init
init
dealloc
push 1
push 2
push 3
push 100
dealloc
dealloc
Regards,
Ryan Joseph
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