Create Comments In Rust

Rust, an open-source systems programming language, allows programmers to write applications with intense performance requirements. This article offers a beginner-friendly introduction on how to create comments in Rust.

Creating Single-line Comments in Rust

In Rust, comments start with // and continue until the end of the line. Here’s a basic example:

// This is a single-line comment in Rust
fn main() {
   // This is another single line comment in Rust
  std::println!("Hello, world!");
}

Code Explanation for Creating Single-line Comments in Rust

The above Rust code is quite self-explanatory, but for those who are new, here’s an overview:

The fn main() {...} syntax is a definition of the main function. This function is automatically called when the program is run. Inside this main function, we have a single-line comment that starts with // The Rust compiler will ignore whatever follows // and until the end of the line.

Below the single-line comment, there is a print statement: std::println!("Hello, world!"); This statement will print the string “Hello, world!” onto your console screen when you run the program. Note that this line of code is not a comment and hence it gets executed.

Creating Multi-line Comments in Rust

Just like single-line comments, Rust also supports multi-line comments which start with /* and end with */, encapsulating any amount of text. Below is an example:

/* This is a Multi-line Comment
And it can span over multiple lines
Ending with the closing tag */
fn main() {
  /* This is how you can
  implement multi-line comments 
  within functions or anywhere in your Rust code*/
  std::println!("Hello, world!");
}

Code Explanation for Creating Multi-line Comments in Rust

The above Rust program starts with a multi-line comment, which spans over three lines. Start a multi-line comment with /* and end it with */. You can write as many lines of comments as you want within this block, and Rust will treat it as one single comment, ignoring everything from the open /* to close */ comment tags.

Just like the previous example, we have a main function defined wherein the functionality of the code is enclosed. There’s also a nested multi-line comment within the function. Finally, std::println!("Hello, world!"); is a line of code to display “Hello, world!” on your console.