A pointer to this opaque data type passes to the C-level function. Some functions in the API accept this pointer as one of their arguments.
A pointer to this opaque data type passes to the C-level function. This data type represents an object, which might be an array object or some other object type.
An opaque data structure that can contain an integer, or a pointer to a floating-point number, string, or object. Some functions in the API can read the values of function arguments by reading the contents of a JSVal structure, and some can be used to write the function’s return value by writing a JSVal structure.