[int_19h]

Coincidentally R is one language in which `if` and `while` can be written as functions, because all function arguments are lazily evaluated, and one can get access to the underlying lambda for repeated re-evaluation. In fact, `if` and `while` are functions in R, and you can call them as such if you properly quote the keyword so that it's treated as an identifier. And then the familiar C-style syntactic forms are just syntactic sugar for function calls.

R takes it up a notch though by making all syntactic constructs boil down to a function call. Function definitions are themselves calls, for example, and so are assignments and even curly braces.