jq is unsurprisingly Turing complete, so I wrote a Whitespace interpreter[0] in jq. It is able to handle real-time I/O by requesting lines on-demand from stdin,

jq is unsurprisingly Turing complete, so I wrote a Whitespace interpreter[0] in jq. It is able to handle real-time I/O by requesting lines on-demand from stdin, which is the main input source, with `input` and outputting strings in a stream. With a relatively large jq program like that, it is critical that the main recursive loop run efficiently, so it's annoying that there's no way to detect whether tail call optimization was applied, other than benchmarking. It would also be nice if object values were lazily evaluated so that it would be possible to create ad hoc switches. [0]: https://github.com/andrewarchi/wsjq https://github.com/andrewarchi/wsjq