Bugl — code interview practice that feels like a game

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Flash cards

Review the key moves

1/4

Core idea

What is the main idea behind Rust Comments?

Lesson checks

Short Mimo-style checks built from this lesson's code, terms, and sequence.

1Quick choice

Which statement best captures the main point of this lesson?

2Fill blank

Complete the missing token from the example code.

// ___ is a comment

3Order

Put the learning moves in the order that makes the concept easiest to apply.

Comments can be used to explain code, and to make it more readable.

Multi-line Comments

Single-line Comments

Comments can be used to explain code, and to make it more readable. It can also be used to prevent execution when testing alternative code.

Comments can be singled-lined or multi-lined .

Single-line comments start with two forward slashes ( // ).

Any text between // and the end of the line is ignored by the compiler (will not be executed).

This example uses a single-line comment before a line of code:

Example

// This is a comment
println!("Hello World!");

This example uses a single-line comment at the end of a line of code:

Example

println!("Hello World!"); // This is a comment

Multi-line comments start with /* and ends with */ .

Any text between /* and */ will be ignored by the compiler:

Example

/* The code below will print the words Hello World! to the screen, and it is
amazing */
println!("Hello World!");

It is up to you which you want to use. Normally, we use // for short comments, and /* */ for longer.