Macro tr 

macro_rules! tr {
    ($c:expr, $id:expr $(,)?) => { ... };
    ($c:expr, $id:expr, $($name:ident = $value:expr),+ $(,)?) => { ... };
}

Look a message up: tr or, with arguments, tr_args.

The first argument is anything with a context (AsContext): a Ui or a Context. Each argument after the id is name = value, the value anything that converts into an Arg.

tr!(ui, "corundum-language")
tr!(ui, "sapphire-version", version = app.version)