> Lisp does have statements, such as `setf` or `loop`. Just because you also attach an expression to it because hey, gotta evaluate to something, doesn't mean

> Lisp does have statements, such as `setf` or `loop`. Just because you also attach an expression to it because hey, gotta evaluate to something, doesn't mean it's not fundamentally a statement. I think the general consensus is that expressions evaluate to values in unexceptional situations, full stop. Whether they have side effects is immaterial. Whether the value returned is useful or not is also immaterial. Perhaps your examples weren't the best, since both setf and loop evaluate to values which are often useful. This isn't just Lisp. For example, the C99 specification explicitly declares that all function calls are expressions, even if they return void. Wikipedia also defines an expression (vs. statement) unambiguously as "a syntactic entity in a programming language that may be evaluated to determine its value.... Expression is often contrasted with statement—a syntactic entity that has no value (an instruction)." https://en.wikipedia.org/wiki/Expression_(computer_science) https://en.wikipedia.org/wiki/Expression_(computer_science)