Keywords

The following words are reserved and may not be used as identifiers. Keywords are case-sensitive and are listed below in ascending order, each linked to the chapter that describes it in full.

Built-in type names (int, bool, char32, …) are not keywords — they are predefined identifiers in the type namespace. For a consolidated list of them, see the Primitive Type Reference.

Keyword	Role
as	Converts a value from one type to another (cast)
asm	Marks a function whose body is written in assembly
break	Exits the nearest enclosing loop
const	Declares a compile-time constant
continue	Skips to the next iteration of a loop
else	Introduces the alternative branch of an if
enum	Declares an enumeration type
extend	Attaches methods to a type, optionally implementing interfaces
extern	Declares a function or symbol defined outside Rux
false	The false boolean value
for	Iterates over the elements of a sequence
func	Declares a function
if	Begins a conditional branch
import	Brings names from a module into scope
in	Separates the loop variable from the sequence in a for loop
interface	Declares an interface
is	Tests whether a value has a given type
let	Declares an immutable variable
loop	Begins an unconditional loop
match	Selects a branch by pattern matching
module	Declares a module (namespace)
null	The null pointer value
pub	Makes an item visible outside its module
return	Returns a value from a function
self	The receiver parameter of a method
struct	Declares a structure type
true	The true boolean value
type	Declares a type alias
union	Declares a union type
var	Declares a mutable variable
while	Loops while a condition holds