DictView.jl provides the types KeysView and ValuesView for dynamic and low-overhead views into the entries (either the keys or the values) of a dictionary. The types implement the start, done, and next methods for iterating over the entries. They further implement the show, eltype, and length methods.
julia> using DictViews
julia> d = ["grass" => "green", "sky" => "blue"]
["sky"=>"blue","grass"=>"green"]
julia> colors() = ValuesView(d)
# method added to generic function colors
julia> for color in colors(); println(color); end
blue
green
julia> d["sky"] = "black"
"black"
julia> colors()
ValuesView{ASCIIString}("black","green")