as: primitive casting, or disambiguating the specific trait containing an item. See Casting Between Types (as), Universal Function Call Syntax (Angle-bracket Form), Associated Types.
break: break out of loop. See Loops (Ending Iteration Early).
const: constant items and constant raw pointers. See const and static, Raw Pointers.
continue: continue to next loop iteration. See Loops (Ending Iteration Early).
crate: external crate linkage. See Crates and Modules (Importing External Crates).
else: fallback for if and if let constructs. See if, if let.
enum: defining enumeration. See Enums.
extern: external crate, function, and variable linkage. See Crates and Modules (Importing External Crates), Foreign Function Interface.
false: boolean false literal. See Primitive Types (Booleans).
fn: function definition and function pointer types. See Functions.
for: iterator loop, part of trait impl syntax, and higher-ranked lifetime syntax. See Loops (for), Method Syntax.
if: conditional branching. See if, if let.
impl: inherent and trait implementation blocks. See Method Syntax.
in: part of for loop syntax. See Loops (for).
let: variable binding. See Variable Bindings.
loop: unconditional, infinite loop. See Loops (loop).
match: pattern matching. See Match.
mod: module declaration. See Crates and Modules (Defining Modules).
move: part of closure syntax. See Closures (move closures).
mut: denotes mutability in pointer types and pattern bindings. See Mutability.
pub: denotes public visibility in struct fields, impl blocks, and modules. See Crates and Modules (Exporting a Public Interface).
ref: by-reference binding. See Patterns (ref and ref mut).
return: return from function. See Functions (Early Returns).
Self: implementor type alias. See Traits.
self: method subject. See Method Syntax (Method Calls).
static: global variable. See const and static (static).
struct: structure definition. See Structs.
trait: trait definition. See Traits.
true: boolean true literal. See Primitive Types (Booleans).
type: type alias, and associated type definition. See type Aliases, Associated Types.
unsafe: denotes unsafe code, functions, traits, and implementations. See Unsafe.
use: import symbols into scope. See Crates and Modules (Importing Modules with use).
where: type constraint clauses. See Traits (where clause).
while: conditional loop. See Loops (while).
Operators and Symbols
! (ident!(…), ident!{…}, ident![…]): denotes macro expansion. See Macros.
! (!expr): bitwise or logical complement. Overloadable (Not).
!= (var != expr): nonequality comparison. Overloadable (PartialEq).
% (expr % expr): arithmetic remainder. Overloadable (Rem).
%= (var %= expr): arithmetic remainder & assignment. Overloadable (RemAssign).
& (expr & expr): bitwise and. Overloadable (BitAnd).
& (&expr, &mut expr): borrow. See References and Borrowing.
& (&type, &mut type, &'a type, &'a mut type): borrowed pointer type. See References and Borrowing.
&= (var &= expr): bitwise and & assignment. Overloadable (BitAndAssign).
&& (expr && expr): logical and.
* (expr * expr): arithmetic multiplication. Overloadable (Mul).
* (*expr): dereference.
* (*const type, *mut type): raw pointer. See Raw Pointers.
*= (var *= expr): arithmetic multiplication & assignment. Overloadable (MulAssign).
+ (expr + expr): arithmetic addition. Overloadable (Add).
+ (trait + trait, 'a + trait): compound type constraint. See Traits (Multiple Trait Bounds).
+= (var += expr): arithmetic addition & assignment. Overloadable (AddAssign).
,: argument and element separator. See Attributes, Functions, Structs, Generics, Match, Closures, Crates and Modules (Importing Modules with use).
- (expr - expr): arithmetic subtraction. Overloadable (Sub).
- (- expr): arithmetic negation. Overloadable (Neg).
-= (var -= expr): arithmetic subtraction & assignment. Overloadable (SubAssign).
-> (fn(…) -> type, |…| -> type): function and closure return type. See Functions, Closures.
. (expr.ident): member access. See Structs, Method Syntax.
.. (.., expr.., ..expr, expr..expr): right-exclusive range literal.
.. (..expr): struct literal update syntax. See Structs (Update syntax).
.. (variant(x, ..), struct_type { x, .. }): "and the rest" pattern binding. See Patterns (Ignoring bindings).
... (...expr, expr...expr) in an expression: inclusive range expression. See Iterators.
... (expr...expr) in a pattern: inclusive range pattern. See Patterns (Ranges).
/ (expr / expr): arithmetic division. Overloadable (Div).
/= (var /= expr): arithmetic division & assignment. Overloadable (DivAssign).
: (pat: type, ident: type): constraints. See Variable Bindings, Functions, Structs, Traits.
: (ident: expr): struct field initializer. See Structs.
: ('a: loop {…}): loop label. See Loops (Loops Labels).
;: statement and item terminator.
; ([…; len]): part of fixed-size array syntax. See Primitive Types (Arrays).
<< (expr << expr): left-shift. Overloadable (Shl).
<<= (var <<= expr): left-shift & assignment. Overloadable (ShlAssign).
< (expr < expr): less-than comparison. Overloadable (PartialOrd).
<= (var <= expr): less-than or equal-to comparison. Overloadable (PartialOrd).
= (var = expr, ident = type): assignment/equivalence. See Variable Bindings, type Aliases, generic parameter defaults.
== (var == expr): equality comparison. Overloadable (PartialEq).
=> (pat => expr): part of match arm syntax. See Match.
> (expr > expr): greater-than comparison. Overloadable (PartialOrd).
>= (var >= expr): greater-than or equal-to comparison. Overloadable (PartialOrd).
>> (expr >> expr): right-shift. Overloadable (Shr).
>>= (var >>= expr): right-shift & assignment. Overloadable (ShrAssign).
@ (ident @ pat): pattern binding. See Patterns (Bindings).
^ (expr ^ expr): bitwise exclusive or. Overloadable (BitXor).
^= (var ^= expr): bitwise exclusive or & assignment. Overloadable (BitXorAssign).
| (expr | expr): bitwise or. Overloadable (BitOr).
| (pat | pat): pattern alternatives. See Patterns (Multiple patterns).
| (|…| expr): closures. See Closures.
|= (var |= expr): bitwise or & assignment. Overloadable (BitOrAssign).
|| (expr || expr): logical or.
_: "ignored" pattern binding (see Patterns (Ignoring bindings)). Also used to make integer-literals readable (see Reference (Integer literals)).
? (expr?): Error propagation. Returns early when Err(_) is encountered, unwraps otherwise. Similar to the try! macro.
'ident: named lifetime or loop label. See Lifetimes, Loops (Loops Labels).
…u8, …i32, …f64, …usize, …: numeric literal of specific type.
"…": string literal. See Strings.
r"…", r#"…"#, r##"…"##, …: raw string literal, escape characters are not processed. See Reference (Raw String Literals).
b"…": byte string literal, constructs a [u8] instead of a string. See Reference (Byte String Literals).
br"…", br#"…"#, br##"…"##, …: raw byte string literal, combination of raw and byte string literal. See Reference (Raw Byte String Literals).
'…': character literal. See Primitive Types (char).
b'…': ASCII byte literal.
|…| expr: closure. See Closures.
path<…> (e.g. Vec<u8>): specifies parameters to generic type in a type. See Generics.
path::<…>, method::<…> (e.g. "42".parse::<i32>()): specifies parameters to generic type, function, or method in an expression. See Generics § Resolving ambiguities.
fn ident<…> …: define generic function. See Generics.
struct ident<…> …: define generic structure. See Generics.
enum ident<…> …: define generic enumeration. See Generics.
impl<…> …: define generic implementation.
for<…> type: higher-ranked lifetime bounds.
type<ident=type> (e.g. Iterator<Item=T>): a generic type where one or more associated types have specific assignments. See Associated Types.
T: U: generic parameter T constrained to types that implement U. See Traits.
T: 'a: generic type T must outlive lifetime 'a. When we say that a type 'outlives' the lifetime, we mean that it cannot transitively contain any references with lifetimes shorter than 'a.
T : 'static: The generic type T contains no borrowed references other than 'static ones.
'b: 'a: generic lifetime 'b must outlive lifetime 'a.
T: ?Sized: allow generic type parameter to be a dynamically-sized type. See Unsized Types (?Sized).
'a + trait, trait + trait: compound type constraint. See Traits (Multiple Trait Bounds).
#[meta]: outer attribute. See Attributes.
#![meta]: inner attribute. See Attributes.
$ident: macro substitution. See Macros.
$ident:kind: macro capture. See Macros.
$(…)…: macro repetition. See Macros.
//: line comment. See Comments.
//!: inner line doc comment. See Comments.
///: outer line doc comment. See Comments.
/*…*/: block comment. See Comments.
/*!…*/: inner block doc comment. See Comments.
/**…*/: outer block doc comment. See Comments.
(): empty tuple (a.k.a. unit), both literal and type.
(expr): parenthesized expression.
(expr,): single-element tuple expression. See Primitive Types (Tuples).
(type,): single-element tuple type. See Primitive Types (Tuples).
(expr, …): tuple expression. See Primitive Types (Tuples).
(type, …): tuple type. See Primitive Types (Tuples).
expr(expr, …): function call expression. Also used to initialize tuple structs and tuple enum variants. See Functions.
ident!(…), ident!{…}, ident![…]: macro invocation. See Macros.
expr.0, expr.1, …: tuple indexing. See Primitive Types (Tuple Indexing).
{…}: block expression.
Type {…}: struct literal. See Structs.
[…]: array literal. See Primitive Types (Arrays).
[expr; len]: array literal containing len copies of expr. See Primitive Types (Arrays).
[type; len]: array type containing len instances of type. See Primitive Types (Arrays).
expr[expr]: collection indexing. Overloadable (Index, IndexMut).
expr[..], expr[a..], expr[..b], expr[a..b]: collection indexing pretending to be collection slicing, using Range, RangeFrom, RangeTo, RangeFull as the "index".