Function Overloads

Many Web APIs are overloaded to take different types of arguments or to skip arguments completely. web-sys contains multiple bindings for these functions that each specialize to a particular overload and set of argument types.

For example, the fetch API can be given a URL string, or a Request object, and it might also optionally be given a RequestInit options object. Therefore, we end up with these web-sys functions that all bind to the window.fetch function:

• Window::fetch_with_str
• Window::fetch_with_request
• Window::fetch_with_str_and_init
• Window::fetch_with_request_and_init

Note that different overloads can use different interfaces, and therefore can require different sets of cargo features to be enabled.