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But how do you know whether a JSON string is a pointer to static data (like in the example with the `main` function) or was dynamically allocated? The same goes for arrays and objects.

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You could tag dynamically allocated objects with some magic bytes. To then check whether a string is dynamically allocated, you can simply compare the first few bytes against the magic bytes. This is a probabilistic method, but if you use enough magic bytes, it becomes basically impossible to go wrong.

See e.g. https://github.com/99991/dynamic/blob/a423a04061ee44bad0720f... for an example (incidentally also a C JSON parser, but with automatic garbage collection).

Hi, author here, i use the 'type' field of the json_value struct, strings, object keys, object values and array members are allocated, i use this info for freeing the memory

So, umm, abusing the C switch statement to implement polymorphism?

I kid, I kid...

I am curious about how much this really saves over just using C++ classes and something like the curiously recurring template pattern while turning off runtime type checking.

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