Loops
There are three looping keywords in Rust: while
, loop
, and for
:
while
The
while
keyword
works much like in other languages, executing the loop body as long as the
condition is true.
fn main() { let mut x = 200; while x >= 10 { x = x / 2; } println!("Final x: {x}"); }
for
The for
loop iterates over
ranges of values:
fn main() { for x in 1..5 { println!("x: {x}"); } }
loop
The loop
statement just
loops forever, until a break
.
fn main() { let mut i = 0; loop { i += 1; println!("{i}"); if i > 100 { break; } } }
This slide should take about 5 minutes.
- We will discuss iteration later; for now, just stick to range expressions.
- Note that the
for
loop only iterates to4
. Show the1..=5
syntax for an inclusive range.