julia> type Foo a::Int end
julia> type Foo a::Int end
julia> type Foo2{T} a::T end
julia> type Foo2{T} a::T endERROR: invalid redefinition of constant Foo2
julia> const a = 11
julia> const a = 2WARNING: redefining constant a2
julia> type Foo2{T} a::T end
julia> type Foo2{T} a::T end
WARNING: did not redefine constant Foo2