ujson Files

This version underwent essential API changes and is no longer compatible with 1.x, though the calling code requires only simple modification to work with the new API.

Breaking Changes

• Val objects (and objects derived from Val, like Bool, Int, etc.) are returned by value (was by reference). Now a Val object includes a pointer to internal data. It acts as lightweight view, similar to std::string_view. The calling code should now look like this (no reference):

cpp ujson::Obj root = json.parse(in).as_obj(); // new API const ujson::Obj& root = json.parse(in).as_obj(); // old API

• get_member(), get_arr_opt(), get_obj_opt() now return a Val, Arr and Obj respectively by value (was pointer). If the value is absent, in the old API this was indicated by nullptr. In the new API this is indicated by bool operator returning false (same as new has_value method). Also in this case get_type() returns vtNone. The application code in such cases looks very similar to how it was before. However, accessing the value now requires a . operator instead of ->:

cpp if (auto obj = parent.get_obj_opt(name)) { int32_t field = obj.get_i32("field"); // was obj->get_i32(...) ... }

New features

• Add Val::has_value() and Val::operator bool(). Comparing to the old API returning a nullptr to indicate an absent value, the new API is much safer and avoids completely accidents of accessing invalid values.
• Add get_member_opt().
• Allow move semantics in Json class so that it can be used in containers.
• Add ref-qualifier in parse() and parse_in_place() to avoid dangling references. Example:

cpp // Now it is compiler error, otherwise val will outlive temporary Json instance: auto val = Json().parse(...);

// This is ok: Json json; auto val = json.parse(...);

Fixes

• Avoid possible compiler undefined behaviour when negating hex numbers. Example: {'x': -0x8000000000000000}. This now is guaranteed to return 0x8000000000000000.