User-defined type used in a module differs from the original

New to Julia
1

I am a newbie with Julia (thigh not with programming in general).
Asn exercise i wanted to some simple 3D geometry modules.

One module for 3D vectors (Vec3D) which includes an overloaded operator “^” for the outer product::

function Base.:^(a::Vec3D, b::Vec3D) 
    Vec3D(a.y*b.z - a.z*b.y,   
                a.z+b.x - a.x*b.z,
               a.x*b.y - a.z*b.y)
end

I then have module for quaternions (Quats)with an operator ^ used for applying a quaternion to a 3D vector:

function Base.:^(a::Quat, b::Vec3D) 
    ...
end

For this to work, i had to include the file containing the Vec3D definitions and import them:

include("vectors3d.jl")
import .Vectors3D:Vec3D

Now, when in julia i include the two files of he the modules, almost everything works as expected. However i have a problem with the quaternions´ “^”-operator;

julia> include("vectors3d.jl")
Main.Vectors3D

julia> include("quats.jl")
Main.quats

julia> using .Vectors3D

julia> using .Quats

julia> a=Vec3D(1,0,0)
Vec3D(1, 0, 0)

julia> q=Quat(0, 0, 0, 1)
Quat(0, 0, 0, 1)

julia> q^a
ERROR: MethodError: no method matching ^(::Quat, ::Vec3D)
Closest candidates are:
    ^(::Quat, ::Main.Quats.Vectors3D.Vec3D) at ~/progs/jl_progs/quats.jl:126
    ^(::Vec3D, ::Vec3D) at ~/progs/jl_progs/vectors3d.jl:50
Stacktrace:
 [1] top-level scope
   @ REPL[8]:1

It looks as if the type of the Vec3D i included and used inside the Quat module is seen as a type different from the Vec3D in the Vectors3D module.

When i define the “^”-operator directly in julia, it works perfectly.

How can i convince julia that the Vec3D type used inside the Quatsmodule is the same as the one from the Vectors3D

2

Import it in the Quats module. You can make this module dependent on the other or, maybe better, make both depend on a third that defines the type.

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