Result type

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In functional programming, a result type is a monadic type holding a returned value or an error code. They provide an elegant way of handling errors, without resorting to exception handling; when a function that may fail returns a result type, the programmer is forced to consider success or failure paths, before getting access to the expected result; this eliminates the possibility of an erroneous programmer assumption.

Contents

Examples

Rust

The result object has the methods is_ok() and is_err().

constCAT_FOUND: bool=true;fnmain(){letresult=pet_cat();ifresult.is_ok(){println!("Great, we could pet the cat!");}else{println!("Oh no, we couldn't pet the cat!");}}fnpet_cat()-> Result<(),String>{ifCAT_FOUND{Ok(())}else{Err(String::from("the cat is nowhere to be found"))}}

See also

Related Research Articles

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References

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