Rust

12.2    Builder Pattern

Some data structures are complicated to construct because they require a large number of inputs and optional configuration choices. This flexibility can easily lead to a large number of distinct constructors, each having many arguments. We suggest the builder pattern make it manageable.

For instance, consider the Customer struct shown in Listing 12.8.

#[derive(Debug, Default, Clone)]struct Customer {    name: String,    username: String,    membership: Membershiptype,    gender: char,    country: String,    age: u8,}#[derive(Debug, Clone)]enum Membershiptype {    new,    causual,    loyal,}impl Default for Membershiptype {    fn default() -> Self {        Membershiptype::new    }}  

Listing 12.8     Definition of Customer Struct Simulating a Complicated Data ...