I mentioned this here earlier, but since then okvs improved things hugely and it's now only a factor of 2 slower than "normal" iterators, which likely makes it useful for anything except critical inner loops.
The basic idea is that you can turn any iterable into something that is "consumed" operation by operation (ie a stream). https://github.com/andrewcooke/StatefulIterators.jl Examples: julia> using StatefulIterators julia> s = StatefulIterator([1,2,3,4,5]) StatefulIterators.StatefulIterator{Array{Int64,1},Int64}([1,2,3,4,5],1) julia> collect(take(s, 2)) 2-element Array{Any,1}: 1 2 julia> eltype(s) Int64 julia> read(s) 3 julia> readbytes(s) 16-element Array{UInt8,1}: 0x04 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x05 0x00 0x00 0x00 0x00 0x00 0x00 0x00
