On Wednesday, 21 October 2015 00:15:41 UTC+10, Matt Bauman wrote:
>
> On Tuesday, October 20, 2015 at 10:09:42 AM UTC-4, Glen O wrote:
>>
>> Seems to be something wrong with the dispatch system with Union...
>>
>
> Yes, Unions with TypeVars can behave strangely when the elements aren't
> mutually exclusive. I think it's just greedily matching the first thing it
> can. In this case it's always matching the `T` in `Union{T,
> AbstractArray{T}}` to the type of the very first argument, and then
> applying that to the remaining arguments, which explains why it works with
> a scalar first argument.
>
That doesn't explain how my test works - if
dispatchtest{T}(x::Union{Array{T,1},T}) = "success"
is called with dispatchtest([1,2]), it fails, even though T=Array{Int,1}
should match.
