mirror of
https://github.com/rust-lang/rustlings
synced 2024-11-18 09:25:36 +00:00
48 lines
764 B
Rust
48 lines
764 B
Rust
// functions5.rs
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// Make me compile! Scroll down for hints :)
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fn main() {
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let answer = square(3);
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println!("The answer is {}", answer);
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}
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fn square(num: i32) -> i32 {
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num * num;
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}
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// This is a really common error that can be fixed by removing one character.
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// It happens because Rust distinguishes between expressions and statements: expressions return
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// a value based on its operand, and statements simply return a () type which behaves just like `void` in C/C++ language.
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// We want to return a value of `i32` type from the `square` function, but it is returning a `()` type...
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// They are not the same. There are two solutions:
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// 1. Add a `return` ahead of `num * num;`
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// 2. remove `;`, make it to be `num * num`
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