Miller is like sed, awk, cut, join, and sort for name-indexed data
such as CSV.
With Miller, you get to use named fields without needing to count
positional indices.
This is something the Unix toolkit always could have done, and
arguably always should have done. It operates on key-value-pair
data while the familiar Unix tools operate on integer-indexed
fields: if the natural data structure for the latter is the array,
then Miller's natural data structure is the insertion-ordered hash
map. This encompasses a variety of data formats, including but not
limited to the familiar CSV. (Miller can handle positionally-indexed
data as a special case.)
