macro, function pointers and operator overloading

function_pointers/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "function_pointers"
+version = "0.1.0"
+authors = ["gbrochar <gaetanbrochard@protonmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

function_pointers/src/main.rs

@@ -0,0 +1,13 @@
+fn add_one(x: i32) -> i32 {
+    x + 1
+}
+
+fn do_twice(f: fn(i32) -> i32, arg: i32) -> i32 {
+    f(arg) + f(arg)
+}
+
+fn main() {
+    let answer = do_twice(add_one, 5);
+
+    println!("The answer is: {}", answer);
+}

hello_macro/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "hello_macro"
+version = "0.1.0"
+authors = ["gbrochar <gaetanbrochard@protonmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+hello_macro_derive = { path = "./hello_macro_derive" }

hello_macro/hello_macro_derive/Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+name = "hello_macro_derive"
+version = "0.1.0"
+authors = ["gbrochar <gaetanbrochard@protonmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+syn = "1.0"
+quote = "1.0"
+
+[lib]
+proc-macro = true

hello_macro/hello_macro_derive/src/lib.rs

@@ -0,0 +1,27 @@
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+use quote::quote;
+use syn;
+
+fn impl_hello_macro(ast: &syn::DeriveInput) -> TokenStream {
+    let name = &ast.ident;
+    let gen = quote! {
+        impl HelloMacro for #name {
+            fn hello_macro() {
+                println!("Hello, Macro! My name is {}!", stringify!(#name));
+            }
+        }
+    };
+    gen.into()
+}
+
+#[proc_macro_derive(HelloMacro)]
+pub fn hello_macro_derive(input: TokenStream) -> TokenStream {
+    // Construct a representation of Rust code as a syntax tree
+    // that we can manipulate
+    let ast = syn::parse(input).unwrap();
+
+    // Build the trait implementation
+    impl_hello_macro(&ast)
+}

hello_macro/src/lib.rs

@@ -0,0 +1,3 @@
+pub trait HelloMacro {
+    fn hello_macro();
+}

hello_macro/src/main.rs

@@ -0,0 +1,9 @@
+use hello_macro::HelloMacro;
+use hello_macro_derive::HelloMacro;
+
+#[derive(HelloMacro)]
+struct Pancakes;
+
+fn main() {
+    Pancakes::hello_macro();
+}

operator_overloading/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "operator_overloading"
+version = "0.1.0"
+authors = ["gbrochar <gaetanbrochard@protonmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

operator_overloading/src/main.rs

@@ -0,0 +1,25 @@
+use std::ops::Add;
+
+#[derive(Debug, PartialEq)]
+struct Point {
+    x: i32,
+    y: i32,
+}
+
+impl Add for Point {
+    type Output = Point;
+
+    fn add(self, other: Point) -> Point {
+        Point {
+            x: self.x + other.x,
+            y: self.y + other.y,
+        }
+    }
+}
+
+fn main() {
+    assert_eq!(
+        Point { x: 1, y: 0 } + Point { x: 2, y: 3 },
+        Point { x: 3, y: 3 }
+    );
+}

pancakes/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "pancakes"
+version = "0.1.0"
+authors = ["gbrochar <gaetanbrochard@protonmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+hello_macro = { path = "../hello_macro" }
+hello_macro_derive = { path = "../hello_macro/hello_macro_derive" }

pancakes/src/main.rs

@@ -0,0 +1,9 @@
+use hello_macro::HelloMacro;
+use hello_macro_derive::HelloMacro;
+
+#[derive(HelloMacro)]
+struct Pancakes;
+
+fn main() {
+    Pancakes::hello_macro();
+}