A Rust While let Statement in Rust is a special statement that basically refractors and allows us to view a clean code. While let statement was inspired by the if let statement in Rust.
Basically in an, if let statement, there is a pattern match and then the block of code gets executed.
if let Some(n) = option {
does_something(n);
}
This statement is equivalent to:
match option {
Some(x) => does_something(n),
_ => {},
}
While let is also similar to the above example.
In Rust, if we write a pattern match and loop, the expression looks like this:
Example 1:
fn main()
{ //gfg -> variable
let mut gfg = "Printing GeeksforGeeks without using while let" .chars();
loop {
match gfg.next() {
Some(x) => print!( "{}" , x),
_ => break ,
}
} println!( "" );
} |
Output:
Now, using the while let statement in Rust. Using while let makes this code easier to read.
Example 2:
fn main()
{ //gfg is a variable
let mut gfg = "Printing GeeksforGeeks using while let" .chars();
while let Some(x) = gfg.next() {
//print is a statement that is used to print characters in one line
print!( "{}" ,x);
}
println!( "\n" );
}
|
Output: