struct Rectangle {

% Method Syntax

<small>There is a new edition of the book and this is an old link.</small>

Methods are different from functions in that they’re defined within the context of a struct, and their first parameter is always self, which represents the instance of the struct the method is being called on.

# struct Rectangle {
#     width: u32,
#     height: u32,
# }

impl Rectangle {
    fn area(&self) -> u32 {
        self.width * self.height
    }
}

Here are the relevant sections in the new and old books:

• in the current edition: Ch 5.03 — Method Syntax
• <small>In the first edition: Ch 3.16 — Method Syntax</small>