There are a few good asumtions about why is faster, there are just speculations since I didn't profile jq or query-json.
The feature that I think penalizes a lot jq is "def functions", the capacity of define any function that can be available during run-time.
This creates a few layers, one of the difference is the interpreter and the linker, the responsible for getting all the builtin functions and compile them have them ready to use at runtime.
The other pain point is the architecture of the operations on top of jq, since it's a stack based. In query-json it's a piped recursive operations.
Aside from the code, the OCaml stack, menhir has been proved to be really fast when creating those kind of compilers.
I will dig more into performance and try to profile both tools in order to improve mine.
Thanks for this. I've been planning a similar work for years and haven't gotten off my ass (too many other projects lol).
I definitely agree that reading from stdin is critical if I'll be able to use it. Don't take the criticism too hard though (especially the "author doesn't appreciate unix" stuff. Sometimes we can be such assholes to each other).
The incompatibility is apparently due to the fact that jq is happy with a concatenation of JSON objects and q is not. For example {'foo':1}{'foo':2} as opposed to [{'foo':1},{'foo':2}]
Yes, but the inputs to jq are not JSON, they are "a sequence of whitespace-separated JSON values which are passed through the provided filter one at a time" which is the relevant thing if you are going to try to replace jq.
The comma operations means that the "filters" are duplicated, so instead of one json state you would pass two if there's one coma; and ofcourse any number of commas are allowed.
The documentation is a problem in the OCaml world and a problem with Reason Native as well. I found myself pretty lost some times, esy.sh should be a initial point in contact for most of Reason related stuff.
Menhir/sedlex and others are pretty high accessibility barrier for new commers.
One of the nice things about all of it it's the discord, it's friendly and always helpful.
Hope it helps, just let me know if there's any specific!
The feature that I think penalizes a lot jq is "def functions", the capacity of define any function that can be available during run-time.
This creates a few layers, one of the difference is the interpreter and the linker, the responsible for getting all the builtin functions and compile them have them ready to use at runtime.
The other pain point is the architecture of the operations on top of jq, since it's a stack based. In query-json it's a piped recursive operations.
Aside from the code, the OCaml stack, menhir has been proved to be really fast when creating those kind of compilers.
I will dig more into performance and try to profile both tools in order to improve mine.
Thanks