Convert bool, int. Often in Rust programs we have bool variables. These can be returned from a function, or from an expression evaluation.
I32 result. By using a cast, we can directly convert a bool to an i32 value. And for non-standard conversions, a match expression can be used.
Required input, output. There are only 2 valid boolean values in programs—true and false. Logically these are usually converted to 1 and 0.
false -> 0
true -> 1
Example code. To begin, we have an example program where we first assign some bools. And then we convert them with the simplest approach, which is an "as" cast.
Part 1 We create some example bools and use 3 different bool variables. We use an expression to set a bool.
Part 2 This is the important part, where the actual conversion from bool to int occurs.
Part 3 We test and print our results. We find that each bool is now the value 0 or 1.
fn main() {
// Part 1: create some example bools.
let result1 = true;
let result2 : bool = false;
let temp = 10;
let result3 = temp == 10 && result1;
// Part 2: convert bools to i32s.
let convert1 = result1 as i32;
let convert2 = result2 as i32;
let convert3 = result3 as i32;
// Part 3: test and print results.
if convert1 == 1 {
println!("TRUE IS 1");
}
println!("{} = {}", result1, convert1);
println!("{} = {}", result2, convert2);
println!("{} = {}", result3, convert3);
}TRUE IS 1
true = 1
false = 0
true = 1
Match example. It is sometimes necessary to use a more complex approach to converting bools. Here we use a logic structure, match, to branch and perform the conversion.
fn main() {
let result1 = true;
// Use match to convert bool with more complex logic.
let convert1 = match result1 {
true => 10,
false => 20
};
println!("{} = {}", result1, convert1);
}true = 10
A summary. Converting bools to i32 values in Rust is easy to do with a cast expression. But more complex or unusual conversions can be done with a match statement as well.
Dot Net Perls is a collection of tested code examples. Pages are continually updated to stay current, with code correctness a top priority.
Sam Allen is passionate about computer languages. In the past, his work has been recommended by Apple and Microsoft and he has studied computers at a selective university in the United States.
