aj-io-tools 0.3.2123

//! Copyright 2023 Dallas
//! 
//! Licensed under the Apache License, Version 2.0 (the "License");
//! you may not use this file except in compliance with the License.
//! You may obtain a copy of the License at
//! 
//! <http://www.apache.org/licenses/LICENSE-2.0>
//! 
//! Unless required by applicable law or agreed to in writing, software
//! distributed under the License is distributed on an "AS IS" BASIS,
//! WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//! See the License for the specific language governing permissions and
//! limitations under the License.

use std::io::{stdin, stdout, Write};
use std::str::FromStr;

/// Scans the input to the console by first 
/// printing an invitation message to the console.
/// 
/// # Params
/// * `message: &str` - Invitation message 
/// to the console.
/// 
/// # Returns
/// * [`String`] object.
/// 
/// # Panics
/// If somehow failed to read line with 
/// `stdin().read_line()` function.
/// 
/// # Examples
/// ```
/// use aj_io_tools::read_line;
/// 
/// let input = read_line("What's your name: ");
/// 
/// match input.as_str() {
///     "Aleksey" => println!("You're Aleksey, glad to hear you!"),
///     _ => println!("You're not Aleksey, but anuway I'm glad to hear you!")
/// }
/// ```
pub fn read_line(message: &str) -> String {
    print!("{message}");

    stdout()
        .flush()
        .unwrap();

    let mut input = String::new();

    stdin()
        .read_line(&mut input)
        .expect("failed to read line.");

    input.trim()
        .to_owned()
}

/// Scans the input to the console by first 
/// printing an invitation message to the console
/// and finally parsing it into a specific type, 
/// declared in turbofish.
/// 
/// # Params
/// * `message: &str` - Invitation message 
/// to the console.
/// 
/// # Returns
/// * Turbofish typed (`T`) object.
/// 
/// # Panics
/// If somehow failed to read line with 
/// `stdin().read_line()` function.
/// 
/// # Examples
/// ```
/// use aj_io_tools::read_line_as;
/// 
/// let input = read_line_as::<u8>("How old are you: ");
/// 
/// match input {
///     23 => println!("Wow, your life is just starting!"),
///     _ => println!("Wow, your life is just starting, but you're not 23!")
/// }
/// ```
pub fn read_line_as<T: Default + FromStr>(message: &str) -> T {
    let input = read_line(message);

    match input.parse::<T>() {
        Ok(n) => n,
        Err(_) => T::default()
    }
}