feat: added excercise for option

Cargo.lock

@@ -592,7 +592,7 @@ dependencies = [
 
 [[package]]
 name = "rustlings"
-version = "2.2.0"
+version = "2.2.1"
 dependencies = [
  "assert_cmd 0.11.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)",

exercises/option/README.md

@@ -0,0 +1,9 @@
+### Option
+
+#### Book Sections
+
+To learn about Option<T>, check out these links:
+
+- [Option Enum Format](https://doc.rust-lang.org/stable/book/ch10-01-syntax.html#in-enum-definitions)
+- [Option Module Documentation](https://doc.rust-lang.org/std/option/)
+- [Option Enum Documentation](https://doc.rust-lang.org/std/option/enum.Option.html)

exercises/option/option1.rs

@@ -0,0 +1,23 @@
+//option1.rs
+//Make me compile! Execute `rustlings hint option1` for hints
+
+//I AM NOT DONE
+
+//you can modify anything EXCEPT for this function's sig
+fn print_number(maybe_number: Option<u16>) {
+    println!("printing: {}", *maybe_number);
+}
+
+fn main() {
+    print_number(13);
+    print_number(99);
+
+    let mut numbers: [Option<u16>; 5];
+    for iter in 0..5 {
+        let number_to_add: u16 = {
+            ((iter * 5) + 2) / (4 * 16);
+        };
+
+        numbers[iter] = number_to_add;
+    }
+}

info.toml

@@ -701,4 +701,18 @@ path = "exercises/conversions/from_str.rs"
 mode = "test"
 hint = """
 If you've already solved try_from_into.rs, then this is almost a copy-paste.
-Otherwise, go ahead and solve try_from_into.rs first."""
+Otherwise, go ahead and solve try_from_into.rs first."""
+
+[[exercises]]
+name = "option1"
+path = "exercises/option/option1.rs"
+mode = "compile"
+hint = """
+Check out some functions of Option:
+is_some
+is_none
+unwrap
+
+and:
+pattern matching
+"""