pascalabcnet/CodeExamples/TypeclassTranslation.pas
2018-04-27 10:35:23 +03:00

33 lines
687 B
ObjectPascal

type
ConceptAttribute = class(System.Attribute)
end;
IsConceptParameterAttribute = class(System.Attribute)
end;
ExplicitModelAttribute = class(System.Attribute)
end;
[Concept] SumTC<T> = abstract class
public
function sum(v1, v2: T): T; abstract;
end;
SumTC_Integer = class(SumTC<integer>)
public
function sum(v1, v2: Integer): Integer; override;
begin
Result := v1 + v2;
end;
end;
function Sum3<T, SumTCT>(v1, v2, v3: T): T; where SumTCT: SumTC<T>, constructor;
begin
var s := __ConceptSingleton&<SumTCT>.&Instance;
Result := s.sum(v1, s.sum(v2, v3));
end;
begin
write(Sum3&<integer, SumTC_integer>(1, 2, 3));
end.