first(permutations(first(combinations(1:2,0)))) type instability

[rleegates]

As the title suggests:

julia> first(permutations(first(combinations(1:2,0))))
0-element Array{Any,1}

[StreetLevel]

Another small example:

While collect is type stable,

julia> collect(permutations(1:N,K))[1]
0-element Array{Int64,1}

first returns a Vector{Any}

julia> first(permutations(1:N,K))
0-element Array{Any,1}

[randy3k]

Here are the results of v0.6, it seems that the issue is fixed.

julia> first(combinations(1:2,0))
0-element Array{Int64,1}

julia> first(permutations(1:2,0))
0-element Array{Int64,1}

julia> first(permutations(first(combinations(1:2,0))))
0-element Array{Int64,1}