A modern version of dominictarr's from, implemented with the new stream api.
var from = require('new-from') var zero_to_nine = from(make_chunk) function make_chunk(idx) { if(idx < 10) { return idx } return null } // Or, in this case: zero_to_nine = from([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])