public/subjects/easy_traits

easy_traits

Instructions

Your task is to implement the trait AppendStr for the type StringValue.

The trait AppendStr has the following functions:

• append_str, that appends to the value of the structure a new_str of type String
• append_number, that appends to the value of the structure a new_number of type f64
• remove_punctuation_marks, that removes from the value of the structure the following punctuation marks: . , ? !

Expected Function

#[derive(Clone)]
struct StringValue {
    value: String,
}

trait AppendStr {
    fn append_str(self, new_str: String) -> Self;

    fn append_number(self, new_number: f64) -> Self;

    fn remove_punctuation_marks(self) -> Self;
}

impl AppendStr for StringValue {
}

Usage

Here is a program to test your function.

use easy_traits::*;

fn main() {
    let mut str_aux = StringValue {
        value: String::from("hello"),
    };

    println!("Before append: {}", str_aux.value);

    str_aux.append_str(String::from(" there!"));
    println!("After append: {}", str_aux.value);

    str_aux.remove_punctuation_marks();
    println!("After removing punctuation: {}", str_aux.value);
}

And its output

$ cargo run
Before append: hello
After append: hello there!
After removing punctuation: hello there
$