`-` unary operator bug?

[ranjanan]

julia -p3

using DistributedArrays
a = rand(1000)
a = distribute(a)
-a

gives the following error:

ERROR: indexing not defined for DistributedArrays.DArray{Float64,1,Array{Float64,1}}
 [inlined code] from ./error.jl:22
 in setindex!(::DistributedArrays.DArray{Float64,1,Array{Float64,1}}, ::Float64, ::CartesianIndex{1}) at ./abstractarray.jl:527
 in -(::DistributedArrays.DArray{Float64,1,Array{Float64,1}}) at ./arraymath.jl:17
 in eval(::Module, ::Any) at ./boot.jl:236

I understand that currently setindex! isn't supported, and should be throwing the above error

[jiahao]

Ref #4