That looks like a bug to me. I couldn't find any github issue covering it,
maybe you should submit one?
On Tuesday, February 16, 2016 at 10:01:05 AM UTC-5, Helge Eichhorn wrote:
>
> When I run the following code
>
> type A
> v::Float64
> end
>
> type B
> v::Float64
> end
>
> Base.convert(::Type{A}, b::B) = A(b.v/2)
> b = B(12)
> A(b)
>
> it fails with this error message because the implicit constructor is
> called.
>
> LoadError: MethodError: `convert` has no method matching
> convert(::Type{Float64}, ::B)
> This may have arisen from a call to the constructor Float64(...),
> since type constructors fall back to convert methods.
> Closest candidates are:
> call{T}(::Type{T}, ::Any)
> convert(::Type{Float64}, !Matched::Int8)
> convert(::Type{Float64}, !Matched::Int16)
> ...
> while loading In[1], in expression starting on line 11
>
> in call at In[1]:2
>
>
> Since the manual said "defining Base.convert(::Type{T}, args...) =
> ...automatically
> defines a constructor T(args...) = ....", I expected this to work.
> If I define a convert method for a built-in type like Float64, it works.
> Am I doing something wrong or is this intended? If so, it should be clearly
> stated in the manual.
>
