pub type Reader = unsafe extern "C-unwind" fn(l: *mut State, ud: *mut c_void, sz: *mut usize) -> *const c_char;Expand description
Function that reads blocks when loading Lua chunks.
Also known as lua_Reader.
§Safety
When a reader function is used by Lua, l always points to a valid Lua
state, ud is always the user-defined data that was passed along with the
reader function, and sz is always a pointer to usize that’s valid for
writes.
The returned value must be a valid pointer to a string, or a null pointer if no data is available. The pointer must be valid for reading at least until the next usage of the function.