Created
March 21, 2014 11:16
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| let x = Some(1); | |
| let y = Some(2); | |
| let z = monad!( | |
| None { | |
| _ => x, | |
| Some(x) => y, | |
| Some(y) => Some(x+y) | |
| } | |
| ); | |
| assert_eq!(z, Some(3)); |
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This works because in Rust you can shadow variable names. Each arm matches against the result of the previous arm. Because the pattern matching allows binding of variables to a name, you can 'unwrap' x and y before adding them together.