Rust 1.43.0

# Documentation

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> Documentation comments use `///` instead of `//` and support Markdown notation for formatting the text if you’d like. You place documentation comments just before the item they are documenting.

    /// Adds one to the number given.
    ///
    /// # Examples
    ///
    /// ```
    /// let five = 5;
    ///
    /// assert_eq!(6, my_crate::add_one(5));
    /// ```
    pub fn add_one(x: i32) -> i32 {
        x + 1
    }

Run

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