My favourite example, because I've been working with it recently, is the nunjucks templating language. It has three or four different ways of almost-but-not-qui

My favourite example, because I've been working with it recently, is the nunjucks templating language. It has three or four different ways of almost-but-not-quite implementing functions. It has dynamic scoping (hello, 1960s!) But my favourite feature is its recursive for-loops. These are truly majestic. I would not believe someone could implement a language so broken if I had not witnessed it.