Initial data commit

Task/Hello-world-Standard-error/Rust/hello-world-standard-error-1.rust

@@ -0,0 +1,3 @@
+fn main() {
+    eprintln!("Hello, {}!", "world");
+}

Task/Hello-world-Standard-error/Rust/hello-world-standard-error-2.rust

@@ -0,0 +1,8 @@
+fn main() {
+    use ::std::io::Write;
+    let (stderr, errmsg) = (&mut ::std::io::stderr(), "Error writing to stderr");
+    writeln!(stderr, "Bye, world!").expect(errmsg);
+
+    let (goodbye, world) = ("Goodbye", "world");
+    writeln!(stderr, "{}, {}!", goodbye, world).expect(errmsg);
+}

Task/Hello-world-Standard-error/Rust/hello-world-standard-error-3.rust

@@ -0,0 +1,10 @@
+fn main() {
+    use std::io::{self, Write};
+
+    io::stderr().write(b"Goodbye, world!").expect("Could not write to stderr");
+    // With some finagling, you can do a formatted string here as well
+    let goodbye = "Goodbye";
+    let world = "world";
+    io::stderr().write(&*format!("{}, {}!", goodbye, world).as_bytes()).expect("Could not write to stderr");
+    // Clearly, if you want formatted strings there's no reason not to just use writeln!
+}