Initial commit

Cargo.lock

+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "bike"
+version = "0.1.0"

Cargo.toml

+[package]
+name = "bike"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]

README.md

+An example of Builder pattern in rust
+
+# Example usage
+
+```rust
+    let builder = Bike::builder();
+    let bike = builder.with_brakes(Brake::Disk)
+        .with_transmission(Transmission::GearHub)
+        .with_wheels(Wheel::Small)
+        .build();
+    
+    println!("{bike:#?}");
+    bike.ride();
+```

src/main.rs

+#![doc = include_str!("../README.md")]
+
+
+#[derive(Debug)]
+pub enum Brake {
+    Disk,
+    Pads
+}
+
+#[derive(Debug)]
+pub enum Wheel {
+    Large,
+    Small,
+}
+
+#[derive(Debug)]
+pub enum Transmission {
+    Standard,
+    GearHub,
+}
+
+#[derive(Debug)]
+pub struct Bike {
+    brakes: Brake,
+    wheels: Wheel,
+    transmission: Transmission,
+}
+
+impl Bike {
+    /// Ride your bike!
+    pub fn ride(&self) {
+        println!("I am riding {:?}", self);
+    }
+    /// Create a new builder to start a bike configuration
+    pub fn builder() -> BikeBuilder {
+        BikeBuilder::default()
+    }
+}
+
+#[derive(Default,Debug)]
+/// A bike builder that helps the configuration of a bike.
+pub struct BikeBuilder {
+    brakes: Option<Brake>,
+    wheels: Option<Wheel>,
+    transmission: Option<Transmission>,
+}
+
+impl BikeBuilder {
+    /// Adds brakes to the bike builder
+    pub fn with_brakes(mut self, brakes: Brake) -> Self {
+        self.brakes = Some(brakes);
+        self
+    }
+    /// Adds wheels to the bike builder
+    pub fn with_wheels(mut self, wheels: Wheel) -> Self {
+        self.wheels = Some(wheels);
+        self
+    }
+    /// Adds a transmission to the bike builder
+    pub fn with_transmission(mut self, transmission: Transmission) -> Self {
+        self.transmission = Some(transmission);
+        self
+    }
+    /// Builds the bike from the builder.
+    ///
+    /// Will panic if the builder configuration is not correct
+    pub fn build(self) -> Bike {
+        Bike {
+            wheels: self.wheels.unwrap(),
+            transmission: self.transmission.unwrap(),
+            brakes: self.brakes.unwrap(),
+        }
+    }
+}
+
+fn main() {
+    let builder = Bike::builder();
+    let bike = builder.with_brakes(Brake::Disk)
+        .with_transmission(Transmission::GearHub)
+        .with_wheels(Wheel::Small)
+        .build();
+    
+    println!("{bike:#?}");
+    bike.ride();
+
+    
+}