Add hello world for Rust

.ijwb/.bazelproject

@@ -1,4 +1,5 @@
 directories:
+  rs
   src
   .
 

WORKSPACE

@@ -171,3 +171,28 @@ maven_install(
     fetch_sources = True,
     repositories = maven_repositories,
 )
+
+## ██████  ██    ██ ███████ ████████
+## ██   ██ ██    ██ ██         ██
+## ██████  ██    ██ ███████    ██
+## ██   ██ ██    ██      ██    ██
+## ██   ██  ██████  ███████    ██
+
+http_archive(
+    name = "rules_rust",
+    sha256 = "0cc7e6b39e492710b819e00d48f2210ae626b717a3ab96e048c43ab57e61d204",
+    urls = [
+        "https://mirror.bazel.build/github.com/bazelbuild/rules_rust/releases/download/0.10.0/rules_rust-v0.10.0.tar.gz",
+        "https://github.com/bazelbuild/rules_rust/releases/download/0.10.0/rules_rust-v0.10.0.tar.gz",
+    ],
+)
+
+load("@rules_rust//rust:repositories.bzl", "rules_rust_dependencies", "rust_register_toolchains")
+
+rules_rust_dependencies()
+
+rust_register_toolchains(edition = "2021")
+
+load("@rules_rust//crate_universe:repositories.bzl", "crate_universe_dependencies")
+
+crate_universe_dependencies()

rs/hello/bin/BUILD

@@ -0,0 +1,7 @@
+load("@rules_rust//rust:defs.bzl", "rust_binary")
+
+rust_binary(
+    name = "bin",
+    srcs = ["main.rs"],
+    deps = ["//rs/hello/greeter"],
+)

rs/hello/bin/main.rs

@@ -0,0 +1,6 @@
+extern crate greeter;
+
+fn main() {
+    let hello = greeter::Greeter::new("Hello");
+    hello.greet("world");
+}

rs/hello/greeter/BUILD

@@ -0,0 +1,10 @@
+package(default_visibility = ["//visibility:public"])
+
+load("@rules_rust//rust:defs.bzl", "rust_library")
+
+rust_library(
+    name = "greeter",
+    srcs = [
+        "greeter.rs",
+    ],
+)

rs/hello/greeter/greeter.rs

@@ -0,0 +1,13 @@
+pub struct Greeter {
+    greeting: String,
+}
+
+impl Greeter {
+    pub fn new(greeting: &str) -> Greeter {
+        Greeter { greeting: greeting.to_string(), }
+    }
+
+    pub fn greet(&self, thing: &str) {
+        println!("{} {}", &self.greeting, thing);
+    }
+}