Why Rust Has Steep Learning Curve

Mar 19, 2023#rust

Rust is often considered to have a steep learning curve because it is a systems programming language that requires a deeper understanding of computer science concepts than some other programming languages.

One of Rust’s main priorities is safety, which means preventing common errors like null pointer dereferences, data races, and buffer overflows.

The steep learning curve of Rust can be attributed to a combination of factors, including its complex ownership and borrowing system, its functional programming concepts, and its syntax.

Despite these challenges, many developers find that Rust’s performance, safety, and expressiveness make it well worth the effort to learn. With practice and persistence, Rust can be a powerful tool for building fast, reliable, and secure software.

Here are a few reasons why Rust can be challenging to learn:

Ownership and borrowing system

Rust’s ownership and borrowing system is a unique feature that ensures memory safety and prevents common programming errors such as data races and null pointer dereferences. However, this system can be challenging for new users to understand, especially if they are not familiar with low-level memory management concepts.

The system ensures that each piece of memory has exactly one owner at any given time and enforces strict rules for borrowing and lifetime of references.

fn main() {
    let mut v = vec![1, 2, 3];

    add_to_vector(&mut v);
    println!("v: {:?}", v);

    let mut s = String::from("hello");
    let r1 = &s;
    let r2 = &s;
    let r3 = &mut s;
    println!("{}, {}, and {}", r1, r2, r3);
}

fn add_to_vector(v: &mut Vec<i32>) {
    v.push(4);
}

This example prevents common errors by enforcing strict rules for ownership and borrowing. By using mutable references to modify the contents of a vector, and by transferring ownership of a mutable string to a single mutable reference, Rust ensures that our code is safe and free of data races.

Low-level programming

Rust is a low-level programming language that is designed to provide the performance of a low-level language like C or C++ while offering the safety and reliability of a high-level language. This combination makes Rust an excellent choice for systems programming (operating systems, embedded systems, device drivers, network stacks), where performance and reliability are critical.

This also means that Rust requires a deeper understanding of computer science concepts such as pointers, memory allocation, and system-level programming.

Another feature of Rust that makes it ideal for low-level programming is its ability to generate code that is as efficient as hand-written assembly code. Rust’s syntax and semantics allow developers to write code that is optimized for the specific hardware it is running on.

One such example Rust is used for developing operating system kernels is Redox OS, a Unix-like operating system written in Rust. Another example is Tokio, a networking stack.

Complex syntax

Rust’s syntax can be more complex than some other programming languages, especially for new users. Rust’s syntax is heavily influenced by C and C++, and includes features such as macros, lifetimes, and pattern matching that can be challenging to understand at first.

Rust’s syntax is intentionally designed to be different from other C-like languages because Rust is a fundamentally different language with different goals and priorities. Rust’s syntax reflects its focus on safety, performance, and concurrency, which are all areas where traditional C-like languages like C, C++, and Java have had problems.

use std::collections::HashMap;

trait Calculate {
    fn calculate(&self) -> i32;
}

struct Rectangle<'a, T: Calculate> {
    height: &'a T,
    width: &'a T,
}

impl<'a, T: Calculate> Rectangle<'a, T> {
    fn new(height: &'a T, width: &'a T) -> Self {
        Rectangle {
            height,
            width,
        }
    }
    
    fn area(&self) -> i32 {
        self.height.calculate() * self.width.calculate()
    }
}

struct Number {
    value: i32,
}

impl Calculate for Number {
    fn calculate(&self) -> i32 {
        self.value
    }
}

macro_rules! print_map {
    ($m:expr) => {
        for (key, value) in $m.iter() {
            println!("{}: {}", key, value);
        }
    };
}

fn main() {
    let number1 = Number { value: 10 };
    let number2 = Number { value: 20 };
    let rectangle = Rectangle::new(&number1, &number2);
    println!("Area of rectangle: {}", rectangle.area());
    
    let mut map = HashMap::new();
    map.insert("one", 1);
    map.insert("two", 2);
    print_map!(map);
    
    let vec1 = vec![1, 2, 3];
    let vec2 = vec![4, 5, 6];
    let (first, second) = match (vec1.first(), vec2.first()) {
        (Some(x), Some(y)) => (x, y),
        _ => panic!("Vectors must have at least one element"),
    };
    println!("First elements of vectors: {}, {}", first, second);
}

This example demonstrates Rust’s support for generics, traits, macros, borrowing, lifetimes, and pattern matching, all of which are essential features for building safe and efficient code in Rust.

Limited ecosystem

Rust is a relatively new programming language that has gained significant popularity in recent years due to its focus on safety, performance, and concurrency. However, one of the drawbacks of Rust is its limited ecosystem. Compared to other popular languages like JavaScript or Python, Rust has a smaller community, fewer libraries and frameworks, and less mature tooling, which can make it harder to get started.

Rust ecosystem is great at offering different options but often there’s not enough data to pick one solution. Oftentimes you hear some strange issues way after you settled on a specific crate.

Rust ecosystem depends very much from developers volunteering their freetime. Many crates are still experimental because just copying other famous libraries does not work well, pretty much re-implementing stuff from scratch.