Reserve some more symbols.

RELEASES.md

@@ -15,6 +15,7 @@ Breaking changes
 * The following `EvalAltResult` variants are removed and merged into `EvalAltResult::ErrorMismatchDataType`: `ErrorCharMismatch`, `ErrorNumericIndexExpr`, `ErrorStringIndexExpr`, `ErrorImportExpr`, `ErrorLogicGuard`, `ErrorBooleanArgMismatch`
 * `Scope::iter_raw` returns an iterator with an additional field indicating whether the variable is constant or not.
 * `rhai::ser` and `rhai::de` namespaces are merged into `rhai::serde`.
+* New reserved symbols: `++`, `--`, `..`, `...`.
 
 New features
 ------------

doc/src/appendix/operators.md

@@ -56,6 +56,10 @@ Symbols and Patterns
 | `/*` .. `*/`                       |       comment        | block comment                         |
 | `(*` .. `*)`                       |       comment        | _reserved_                            |
 | `<` .. `>`                         |   angular brackets   | _reserved_                            |
+| `++`                               |      increment       | _reserved_                            |
+| `--`                               |      decrement       | _reserved_                            |
+| `..`                               |        range         | _reserved_                            |
+| `...`                              |        range         | _reserved_                            |
 | `#`                                |         hash         | _reserved_                            |
 | `@`                                |          at          | _reserved_                            |
 | `$`                                |        dollar        | _reserved_                            |

src/token.rs

@@ -1205,6 +1205,10 @@ fn get_next_token_inner(
                 eat_next(stream, pos);
                 return Some((Token::PlusAssign, start_pos));
             }
+            ('+', '+') => {
+                eat_next(stream, pos);
+                return Some((Token::Reserved("++".into()), start_pos));
+            }
             ('+', _) if !state.non_unary => return Some((Token::UnaryPlus, start_pos)),
             ('+', _) => return Some((Token::Plus, start_pos)),
 
@@ -1218,6 +1222,10 @@ fn get_next_token_inner(
                 eat_next(stream, pos);
                 return Some((Token::Reserved("->".into()), start_pos));
             }
+            ('-', '-') => {
+                eat_next(stream, pos);
+                return Some((Token::Reserved("--".into()), start_pos));
+            }
             ('-', _) if !state.non_unary => return Some((Token::UnaryMinus, start_pos)),
             ('-', _) => return Some((Token::Minus, start_pos)),
 
@@ -1282,12 +1290,22 @@ fn get_next_token_inner(
 
             (';', _) => return Some((Token::SemiColon, start_pos)),
             (',', _) => return Some((Token::Comma, start_pos)),
+
+            ('.', '.') => {
+                eat_next(stream, pos);
+
+                if stream.peek_next() == Some('.') {
+                    eat_next(stream, pos);
+                    return Some((Token::Reserved("...".into()), start_pos));
+                } else {
+                    return Some((Token::Reserved("..".into()), start_pos));
+                }
+            }
             ('.', _) => return Some((Token::Period, start_pos)),
 
             ('=', '=') => {
                 eat_next(stream, pos);
 
-                // Warn against `===`
                 if stream.peek_next() == Some('=') {
                     eat_next(stream, pos);
                     return Some((Token::Reserved("===".into()), start_pos));