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src/about.md

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-# Rust By Practice
-
-This book was designed for easily diving into Rust, and it's very easy to use: All you need to do is to make each exercise compile without ERRORS and Panics !
-
-## Read online
-
-- [English](https://practice.rs)
-- [简体中文](https://zh.practice.rs)
-
-## Features
-
-Part of our examples and exercises are borrowed from [Rust By Example](https://github.com/rust-lang/rust-by-example), thanks for your great works!
-
-Although they are so awesome, we have our own secret weapons :)
-
-- There are three parts in each chapter: examples, exercises and practices
-
-- Besides examples, we have `a lot of exercises`, you can Read, Edit and Run them ONLINE
-
-- Covering nearly all aspects of Rust, such as async/await, threads, sync primitives, optimizing and standard libraries** etc.
-
-- Every exercise has its own solutions
-
-- The overall difficulties are a bit higher and from easy to super hard: easy 🌟 medium 🌟🌟 hard 🌟🌟🌟 super hard 🌟🌟🌟🌟
-
-**What we want to do is fill in the gap between learning and getting started with real projects.**
-
-## Some of our exercises
-
-🌟🌟🌟 Tuple struct looks similar to tuples, it has added meaning the struct name provides but has no named fields. It's useful when you want give the whole tuple a name, but don't care the fields's names.
-
-```rust
-
-// fix the error and fill the blanks
-struct Color(i32, i32, i32);
-struct Point(i32, i32, i32);
-fn main() {
-    let v = Point(___, ___, ___);
-    check_color(v);
-}
-
-fn check_color(p: Color) {
-    let (x, _, _) = p;
-    assert_eq!(x, 0);
-    assert_eq!(p.1, 127);
-    assert_eq!(___, 255);
- }
-```
-
-🌟🌟 Within the destructuring of a single variable, both by-move and by-reference pattern bindings can be used at the same time. Doing this will result in a partial move of the variable, which means that parts of the variable will be moved while other parts stay. In such a case, the parent variable cannot be used afterwards as a whole, however the parts that are only referenced (and not moved) can still be used.
-```rust
-
-// fix errors to make it work
-#[derive(Debug)]
-struct File {
-    name: String,
-    data: String,
-}
-fn main() {
-    let f = File {
-        name: String::from("readme.md"),
-        data: "Rust By Practice".to_string()
-    };
-
-    let _name = f.name;
-
-    // ONLY modify this line
-    println!("{}, {}, {:?}",f.name, f.data, f);
-}
-```
-
-🌟🌟 A match guard is an additional if condition specified after the pattern in a match arm that must also match, along with the pattern matching, for that arm to be chosen.
-```rust,editable
-
-// fill in the blank to make the code work, `split` MUST be used
-fn main() {
-    let num = Some(4);
-    let split = 5;
-    match num {
-        Some(x) __ => assert!(x < split),
-        Some(x) => assert!(x >= split),
-        None => (),
-    }
-}
-```