I found this approach in Rotations.jl. Why code it this way? Note that AngleAxis is a concrete type, so AA can only be one type. @inline function (::Type{AA})(q::QuatRotation) where AA <: AngleAxis w = real(q.q) x, y, z = imag_part(q.q) s2 = x * x + y * y + z * z sin_t2 = sqrt(s2) …

No the signatures look the same AFAICT. These aren’t really callable structs. It is a strange way to write a constructor, but I can’t seem to find a difference. This can be used to do certain “Abstract” constructors but AngleAxis is a struct so I’m not sure the purpose.

Are these type functors the same as Outer Constructors?

General Usage

Oscar_Smith February 22, 2024, 6:53pm 2

No. These are callable structs (see Function factories or callable structs?)

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Are these type functors the same as Outer Constructors?

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