implement comments

src/parser.rs

@@ -353,7 +353,36 @@ impl<'a> Iterator for TokenIterator<'a> {
                 '+' => return Some(Token::Plus),
                 '-' => return Some(Token::Minus),
                 '*' => return Some(Token::Multiply),
-                '/' => return Some(Token::Divide),
+                '/' => {
+                    match self.char_stream.peek() {
+                        Some(&'/') => {
+                            self.char_stream.next();
+                            while let Some(c) = self.char_stream.next() {
+                                if c == '\n' { break; }
+                            }
+                        }
+                        Some(&'*') => {
+                            let mut level = 1;
+                            self.char_stream.next();
+                            while let Some(c) = self.char_stream.next() {
+                                match c {
+                                    '/' => if let Some('*') = self.char_stream.next() {
+                                        level+=1;
+                                    }
+                                    '*' => if let Some('/') = self.char_stream.next() {
+                                        level-=1;
+                                    }
+                                    _ => (),
+                                }
+
+                                if level == 0 {
+                                    break;
+                                }
+                            }
+                        }
+                        _ => return Some(Token::Divide),
+                    }
+                }
                 ';' => return Some(Token::Semicolon),
                 ':' => return Some(Token::Colon),
                 ',' => return Some(Token::Comma),

src/tests.rs

@@ -401,3 +401,12 @@ fn test_array_with_structs() {
         assert!(false);
     }
 }
+
+#[test]
+fn test_comments() {
+	let mut engine = Engine::new();
+
+	assert!(engine.eval::<i64>("let x = 5; x // I am a single line comment, yay!").is_ok());
+
+	assert!(engine.eval::<i64>("let /* I am a multiline comment, yay! */ x = 5; x").is_ok());
+}