I found something sneaky I'd like to confirm before I decide what to do about
it.
1) "T" in TAnyClass<T> is specialized as Integer from the first parameter with
TSomeClass (which is TAnyClass<Integer>).
2) "U" is getting specialized as String by looking at the parameters in
Compare() in which "U"(the second generic parameter) is String.
This specializes the procedure correctly but it uses a very sneaky method which
is very hard to discern. I feel like that if a generic parameter is already
used (like T in specialize TCallback<T, U>) then no further attempt should be
made to look at the parameters and in the example below "U" would not be found
and the function would fail to implicitly specialize.
==============================
type
generic TAnyClass<U> = class
type TElem = U;
end;
type
TSomeClass = specialize TAnyClass<Integer>;
type
generic TCallback<T, U> = function(a: T; b: U): integer;
function Compare(a: TSomeClass.TElem; b: string): integer;
begin
result := 1;
end;
generic procedure DoThis<T, U>(aClass: specialize TAnyClass<T>; callback:
specialize TCallback<T, U>);
begin
callback(1, 'string');
end;
begin
DoThis(TSomeClass.Create, @Compare);
end.
Regards,
Ryan Joseph
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