(nil 3 4) is a completely valid program if the "nil" symbol is bound to a lambda, so I'd argue that yes, it is still homoiconic. If you're looking for a langua

(nil 3 4) is a completely valid program if the "nil" symbol is bound to a lambda, so I'd argue that yes, it is still homoiconic. If you're looking for a language where every valid data structure is a semantically valid program - it doesn't exist.