> What do you think about making the tokenizer, that is now called
> json-tokens, an optional argument of json-fold?  Since it is easy to
> implement json-read with json-fold, I would not propagate the optional
> argument to json-read to keep the signature simpler.  Eventually, it
> would be easier to somehow handle unpaired surrogates.

A JSON fold makes sense. But if `json-tokens` is a generator, the
generic `generator-fold` from SRFI 158 should be usable on it; do we
need a custom fold just for JSON?