what is the equal to a C++ STD::SET<Type> enumerator

[jamie]

as it states in the title. In this case its only one TYPE and I assume that it must not allow duplicates of values.

Also this SET has an enumerator, So I for now am using a TFPGList and the enumerator Generic, but something tells me that is wrong, but it gets me out of the hole until I can get the converted app to actually do something.

[ASerge]

as it states in the title. In this case its only one TYPE and I assume that it must not allow duplicates of values.

Also this SET has an enumerator, So I for now am using a TFPGList and the enumerator Generic, but something tells me that is wrong, but it gets me out of the hole until I can get the converted app to actually do something.

And why are the usual sets not suitable?

[jamie]

https://en.cppreference.com/w/cpp/container/set

This is dynamic so one can add,Delete unique values.

[Thaddy]

rtl-generics: TCustomSet/tHashset in generics.collections.
fcl-stl: gHashSet
fcl-stl is inspired by C++ functionality of stl::<class> so may come closest.
rtl-generics sets are just as good. fgl does not have sets afaik.
avk's lgenerics has a variety of sets (install via OPM or https://github.com/avk959/LGenerics ) firmly founded in theory and with a nice comprehensive wiki entry.
The c++ set you mention is in fact a hash set.
For generics.collections I have put a series of pascal set operator overloads somewhere, but you seem to want something close to C++ instead of pascal set notation, so probably not relevant to you.
In general, but given its limitations, normal pascal sets should be used. I do not quite understand why you can't use Pascal sets? But there are plenty of good implementations.

[jamie]

Something like this code.

Code: Pascal  [Select][+][-]

1. unit Unit1;
2.  
3. {$mode objfpc}{$H+}
4.  
5. interface
6.  
7. uses
8.   Classes, SysUtils, Forms, Controls, Graphics, Dialogs, StdCtrls,fgl;
9.  
10. type
11.  generic TSet<T> = Class(Specialize TFPGList<T>)
12.    Private
13.     Type
14.      fArrayType = Array of T;
15.   Public
16.    constructor Create(A:fArrayType);
17.   End;
18.  
19.   { TForm1 }
20.  
21.   TForm1 = class(TForm)
22.     Button1: TButton;
23.     procedure Button1Click(Sender: TObject);
24.   private
25.  
26.   public
27.  
28.   end;
29.  
30. var
31.   Form1: TForm1;
32.  
33. implementation
34.  
35. {$R *.lfm}
36. constructor TSet.Create(A:fArrayType);
37. Var
38.   AA:T;
39. Begin
40.   Inherited Create;
41.   For AA in A do
42.   if Self.IndexOf(AA)<0 Then
43.    Add(AA); {Else Optional fault trigger}
44. end;
45.  
46. { TForm1 }
47.  
48. procedure TForm1.Button1Click(Sender: TObject);
49. Type
50.   TS = Specialize TSet<Byte>;
51. Var
52.   S:TS;
53. begin
54.   S:= TS.Create([1,2,4,5]); //Should not duplicate
55.   Caption := S.Count.Tostring;
56.   S.Free;
57. end;
58.  
59. end.
60.  
61.  

[Thaddy]

That is exactly what all the sets I mentioned do: of course they do not duplicate, because they are sets. Sets only contain unique values by definition. They also need to implement the set operators/functions except maybe symmetric difference.(><)
The latter is not implemented in C++ std library nor in many other sets in different languages. In your case I would use the fcl-stl set or implement one for fgl. That is not difficult, rather basic stuff. implement include, exclude and contains and it is a set. A set needs not be ordered, although Pascal sets are ordered by nature. In C++ the std library is a hash set, because that allows for fast membership determination, given the unordered nature of a mathematical set. All other operants can be done by testing for membership.
Hence you only need the three basics: add/include, remove/exclude, contains. So if you want to stick to fgl, you know what you need to do 
Tip: the underlying structure of a set is not an array but a list, you link and unlink elements of a list.
[edit]
In fgl, TFpsMap with duplicates is dupError or dupIgnore is already a set.....
I wanted to implement it for you, but the code is already there.