On Monday, October 5, 2015 at 8:34:35 AM UTC-4, Maxim Berman wrote:
>
> Hello,
>
> I tried to use element-wise equality on list-of-lists in julia:
>
> L = Vector{Int}[[1,2],[2,3]]
> B = (L .== L[1])
>
> However, due to .== broadcasting, this last expression performs an
> elementwise operation on the two arrays, and therefore returns [false,
> false]. I don't believe there is a way to circumvent this behavior, since
> .== is meant to do both array-to-element and array-to-arrays
> comparison...
>
You could define a special `.==` method of the form
import Base: .==
.=={T}(A::AbstractArray{T}, b::T) = Bool[a == b for a in A]
.=={T}(b::T, A::AbstractArray{T} = A .== b
to allow .== to work for the case you want without screwing up element-wise
comparison for other cases.
