29 wiersze
786 B
Rust
29 wiersze
786 B
Rust
//-- #########################
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//-- Task: Implementing mapt for Result
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//-- Author: Vigneshwer.D
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//-- Version: 1.0.0
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//-- Date: 26 March 17
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//-- #########################
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use std::num::ParseIntError;
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// Define a generic alias for a `Result` with the error type `ParseIntError`.
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type AliasedResult<T> = Result<T, ParseIntError>;
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// Use the above alias to refer to our specific `Result` type.
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fn double_number(number_str: &str) -> AliasedResult<i32> {
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number_str.parse::<i32>().map(|n| 2 * n)
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}
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// Here, the alias again allows us to save some space.
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fn print(result: AliasedResult<i32>) {
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match result {
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Ok(n) => println!("n is {}", n),
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Err(e) => println!("Error: {}", e),
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}
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}
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fn main() {
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print(double_number("10"));
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print(double_number("t"));
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} |