I'm absolutely positively in love with "Universal function call syntax" from D, it makes the following: foo.bar(baz) compile to the following if foo has n

I'm absolutely positively in love with "Universal function call syntax" from D, it makes the following: foo.bar(baz) compile to the following if foo has no property bar: bar(foo, baz) It allows you to trivially extend classes from libraries without meddling with their code or breaking other code using the library. e.g. if you define: string helloWorldize(string input){ return "Hello, "~input; } You can then do this anywhere "helloWorldize" is in scope: "bob".helloWorldize(); And because of the strong type system and smart compiler you'll never run into situations where you call helloWorldize when you don't mean to.