You could still do it as a userland feature and implement add/sub/mult/div as methods on the type.
That never works as well as having it built into the compiler.
You can define your own "built-ins" types and functions(!) so that should make it indistinguishable.
You can also extend the standard Library from inside your own project, modules are open for extension
That never works as well as having it built into the compiler.
You can define your own "built-ins" types and functions(!) so that should make it indistinguishable.
You can also extend the standard Library from inside your own project, modules are open for extension