This is an attribute macro that expands to dynamically linked code. All functions declared are expanded into thunks. Vulkan and Opengl have specializations at the time of expansion. This crate does not work on its own, because it needs a reverse dependency for its definitions.
The following is the minimum dependency required for macro expansion:
* once_cell = "1.4.0"
The following are the minimum functions that need a definition:
rs
pub fn vkloader(&str, Context) -> *const c_void; // Vulkan specialization
pub fn glloader(&str) -> *const c_void; // Opengl specialization
pub fn loader(&str, &str) -> *const c_void; // Generalization