Rust has an extremely powerful control flow operator called match that allows you to compare a value against a series of patterns and then execute code based on which pattern matches. Patterns can be made up of literal values, variable names, wildcards, and many other things; (source)
Match statement are kind of similar to switch statements; below is an example of how to use a match statements in rust
let country_code = 234;
let country = match country_code{
44 => "United Kingdom",
234 => "Nigeria",
7 => "Russia",
1 => "USA",
_ => "Unknown"
};
println!("the country with code {} is {}", country_code, country)
OUTPUT: "the country with code 234 is Nigeria"
The Breakdown;
- 1) The match control flow operation begins with the match keyword followed by the value or variable used for comparison.
- 2) After the keyword and variable is the expression. the match expressions are encapsulated within curly brackets.
3) In the expression, the left hand side is the pattern and the right hand side is the code executed when the pattern matches, here we are returning a string value.
Notice the
_
pattern at the bottom?. The _ pattern is a special pattern that will match any value. By putting it after our other arms, the _ will match all the possible cases that aren’t specified before it.
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