Rust Pattern Matching Basic pattern matching
Example
// Create a boolean value
let a = true;
// The following expression will try and find a pattern for our value starting with
// the topmost pattern.
// This is an exhaustive match expression because it checks for every possible value
match a {
true => println!("a is true"),
false => println!("a is false")
}
If we don't cover every case we will get a compiler error:
match a {
true => println!("most important case")
}
// error: non-exhaustive patterns: `false` not covered [E0004]
We can use _ as the default/wildcard case, it matches everything:
// Create an 32-bit unsigned integer
let b: u32 = 13;
match b {
0 => println!("b is 0"),
1 => println!("b is 1"),
_ => println!("b is something other than 0 or 1")
}
This example will print:
a is true
b is something else than 0 or 1
