Do you put return type in function definitions?

[greatpet]

That’s right. Converting from Vector to AbstractVector has no actual effect, so the annotation becomes just a type assertion.

[stevengj]

@Vincent_Picaud

However I generally used return type annotations when I wanted to clarify my “interfaces”.

That’s not really what return-type annotations are for. Just use comments or docstrings.

[Steven_Sagaert]

disagree on this. comments are not checked, type annotations are.

[stevengj]

@Steven_Sagaert

comments are not checked, type annotations are.

I was responding to a comment about using return-type declarations to “clarify”, i.e. document.

And return-type annotations are “enforced” by calling convert in Julia, which means that they aren’t necessarily a validation mechanism — they can hide a type-instability.