let num = 1 ;
if num > 0 {
// statements
} else if num == 1 {
// statements
} else {
// statements
}
let condition = true ;
let num = if condition { 5 } else { 6 } ;
Rust has three kinds of loops: loop
, while
, and for
.
Executes a block of code over and over again forever until explicitly exited.
break
and continue
can be used to control the execution of the loop
.
break
can also be used to return a value from the loop while simultaneously exiting the loop.
Loops can also be labeled which is helpful in disambiguation where nested loops with break
or continue
statements are used.
fn main ( ) {
let mut condition = 0 ;
let result = loop {
counter += 1 ;
if counter == 10 {
break counter * 2 ; // Return value. Technicaly an expression.
}
} ;
' counting_up: loop { // loop label
// statements
break ' counting_up
}
}
Conditional Loops with while
let num = 2 ;
while num != 0 {
// statements
}
Looping through a Collection with for
Most commonly used loop construct in Rust due to the conciseness and safety.
let a = [ 1 , 2 , 3 , 4 ] ;
for element in a {
// statemnts
}
for num in ( 1 ..4 ) { // specify number range
// statements
}