Change Option<> in

parse_orientation()
parse_instruction()
for Result<Instruction, &'static str>

src/main.rs

@@ -11,22 +11,22 @@ enum Instruction {
     F,
 }
 
-fn parse_orientation(c: char) -> Option<Orientation> {
+fn parse_orientation(c: char) -> Result<Orientation, &'static str> {
     match c {
-        'N' => Some(Orientation::N),
-        'E' => Some(Orientation::E),
-        'S' => Some(Orientation::S),
-        'W' => Some(Orientation::W),
-        _ => None,
+        'N' => Ok(Orientation::N),
+        'E' => Ok(Orientation::E),
+        'S' => Ok(Orientation::S),
+        'W' => Ok(Orientation::W),
+        _ => Err("Invalid character, does not match any orientations"),
     }
 }
 
-fn parse_instruction(c: char) -> Option<Instruction> {
+fn parse_instruction(c: char) -> Result<Instruction, &'static str> {
     match c {
-        'L' => Some(Instruction::L),
-        'R' => Some(Instruction::R),
-        'F' => Some(Instruction::F),
-        _ => None,
+        'L' => Ok(Instruction::L),
+        'R' => Ok(Instruction::R),
+        'F' => Ok(Instruction::F),
+        _ => Err("Invalid character, does not match any instructions"),
     }
 }