Hi all Someone can explain me ( because apparently i'm stupid... 😦 ) why :

[bold totem]

@teal snow : +1 for thread i don't seen ^^
In fact i forgot the public keywork in example sorry

[teal snow]

did you forget the ; after class definitions too though

also, is this all in the same file

@bold totem

[bold totem]

Sorry i edited my message again : the ; is here in my real code

and in my real code .h and .cpp too

[teal snow]

for template functions, the implementation should be in the header too

if the A::GetEvents implementation is in a cpp, that could cause the unresollved external

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oh .. ty i'm really stupid in fact ^^ 🙏

@teal snow
It's works 🙂
what time wasted for so little but you just opened the way for me
I understand better a lot of things that happened to me 🙏 🙏