Keywords

Question 1

as

Answer 1

perform primitive casting, disambiguate the specific trait containing an item, or rename items in use and extern crate statements

Question 2

async

Answer 2

return a Future instead of blocking the current thread

Question 3

await

Answer 3

suspend execution until the result of a Future is ready

Question 4

break

Answer 4

exit a loop immediately

Question 5

const

Answer 5

define constant items or constant raw pointers

Question 6

continue

Answer 6

continue to the next loop iteration

Question 7

crate

Answer 7

link an external crate or a macro variable representing the crate in which the macro is defined

Question 8

dyn

Answer 8

dynamic dispatch to a trait object

Question 9

else

Answer 9

fallback for if and if let control flow constructs

Question 10

enum

Answer 10

define an enumeration

Question 11

extern

Answer 11

link an external crate, function, or variable

Question 12

false

Answer 12

Boolean false literal

Question 13

fn

Answer 13

define a function or the function pointer type

Question 14

for

Answer 14

loop over items from an iterator, implement a trait, or specify a higher-ranked lifetime

Question 15

if

Answer 15

branch based on the result of a conditional expression

Question 16

impl

Answer 16

implement inherent or trait functionality

Question 17

in

Answer 17

part of for loop syntax

Question 18

let

Answer 18

bind a variable

Question 19

loop

Answer 19

loop unconditionally

Question 20

match

Answer 20

match a value to patterns

Question 21

mod

Answer 21

define a module

Question 22

move

Answer 22

make a closure take ownership of all its captures

Question 23

mut

Answer 23

denote mutability in references, raw pointers, or pattern bindings

Question 24

pub

Answer 24

denote public visibility in struct fields, impl blocks, or modules

Question 25

ref

Answer 25

bind by reference

Question 26

return

Answer 26

return from function

Question 27

Self

Answer 27

a type alias for the type we are defining or implementing

Question 28

self

Answer 28

method subject or current module

Question 29

static

Answer 29

global variable or lifetime lasting the entire program execution

Question 30

struct

Answer 30

define a structure

Question 31

super

Answer 31

parent module of the current module

Question 32

trait

Answer 32

define a trait

Question 33

true

Answer 33

Boolean true literal

Question 34

type

Answer 34

define a type alias or associated type

Question 35

union

Answer 35

define a union and is only a keyword when used in a union declaration

Question 36

unsafe

Answer 36

denote unsafe code, functions, traits, or implementations

Question 37

use

Answer 37

bring symbols into scope

Question 38

where

Answer 38

denote clauses that constrain a type

Question 39

while

Answer 39

loop conditionally based on the result of an expression

Question 40

raw identifiers

Answer 40

Raw identifiers are the syntax that lets you use keywords where they wouldn’t normally be allowed.

You use a raw identifier by prefixing a keyword with r#.

Raw identifiers allow you to use any word you choose as an identifier, even if that word happens to be a reserved keyword.

In addition, raw identifiers allow you to use libraries written in a different Rust edition than your crate uses.