What is the Rust equivalent to a try-catch statement?

Question

Is it possible to handle multiple different errors at once instead of individually in Rust without using additional functions? In short: what is the Rust eq

Answer 1

Results in Rust can be chained using and_then. So you can do this:

if let Err(e) = do_step_1().and_then(do_step_2).and_then(do_step_3) {
    println!("Failed to perform necessary steps");
}

or if you want a more compact syntax, you can do it with a macro:

macro_rules! attempt { // `try` is a reserved keyword
   (@recurse ($a:expr) { } catch ($e:ident) $b:block) => {
      if let Err ($e) = $a $b
   };
   (@recurse ($a:expr) { $e:expr; $($tail:tt)* } $($handler:tt)*) => {
      attempt!{@recurse ($a.and_then (|_| $e)) { $($tail)* } $($handler)*}
   };
   ({ $e:expr; $($tail:tt)* } $($handler:tt)*) => {
      attempt!{@recurse ($e) { $($tail)* } $($handler)* }
   };
}

attempt!{{
   do_step1();
   do_step2();
   do_step3();
} catch (e) {
   println!("Failed to perform necessary steps: {}", e);
}}

playground