feat: 添加数组字面量和索引访问功能，更新解析器和解释器以支持数组操作

src/interpreter/interpreter.rs

@@ -159,6 +159,54 @@ impl Interpreter {
                     }),
                 }
             }
+            Expr::IndexGet { array, index } => {
+                let arr = self.evaluate(*array)?;
+                let idx = self.evaluate(*index)?;
+                let i = self.as_array_index(&idx)?;
+                match arr {
+                    Value::Array(vec) => {
+                        let vec = vec.borrow();
+                        vec.get(i).cloned().ok_or_else(|| RuntimeError::RuntimeError {
+                            message: format!("Index {} out of bounds (len {})", i, vec.len()),
+                            token: None,
+                        })
+                    }
+                    Value::String(s) => {
+                        let chars: Vec<char> = s.chars().collect();
+                        chars.get(i).map(|&c| Value::String(c.to_string())).ok_or_else(|| RuntimeError::RuntimeError {
+                            message: format!("Index {} out of bounds (len {})", i, chars.len()),
+                            token: None,
+                        })
+                    }
+                    _ => Err(RuntimeError::RuntimeError {
+                        message: "Index access on non-array, non-string value".to_string(),
+                        token: None,
+                    }),
+                }
+            }
+            Expr::IndexSet { array, index, value } => {
+                let arr = self.evaluate(*array)?;
+                let idx = self.evaluate(*index)?;
+                let val = self.evaluate(*value)?;
+                let i = self.as_array_index(&idx)?;
+                match arr {
+                    Value::Array(vec) => {
+                        let mut vec = vec.borrow_mut();
+                        if i >= vec.len() {
+                            return Err(RuntimeError::RuntimeError {
+                                message: format!("Index {} out of bounds (len {})", i, vec.len()),
+                                token: None,
+                            });
+                        }
+                        vec[i] = val.clone();
+                        Ok(val)
+                    }
+                    _ => Err(RuntimeError::RuntimeError {
+                        message: "Index assignment on non-array value".to_string(),
+                        token: None,
+                    }),
+                }
+            }
             Expr::ObjectLiteral { properties } => {
                 let mut map = HashMap::new();
                 for (key, value_expr) in properties {
@@ -167,6 +215,13 @@ impl Interpreter {
                 }
                 Ok(Value::Object(Rc::new(RefCell::new(map))))
             }
+            Expr::ArrayLiteral { elements } => {
+                let mut arr = Vec::new();
+                for e in elements {
+                    arr.push(self.evaluate(e)?);
+                }
+                Ok(Value::Array(Rc::new(RefCell::new(arr))))
+            }
             Expr::Unary { op, right } => {
                 let val = self.evaluate(*right)?;
                 match op {
@@ -303,6 +358,12 @@ impl Interpreter {
             (Value::Bool(x), Value::Bool(y)) => x==y,
             (Value::Number(x), Value::Number(y)) => x==y,
             (Value::String(x), Value::String(y)) => x==y,
+            (Value::Array(x), Value::Array(y)) => {
+                let x = x.borrow();
+                let y = y.borrow();
+                if x.len() != y.len() { return false; }
+                x.iter().zip(y.iter()).all(|(a,b)| self.is_equal(a,b))
+            }
             _ => false,
         }
     }
@@ -317,5 +378,22 @@ impl Interpreter {
             })
         }
     }
+
+    fn as_array_index(&self, val: &Value) -> Result<usize, RuntimeError> {
+        if let Value::Number(n) = val {
+            if *n < 0.0 || n.fract() != 0.0 {
+                return Err(RuntimeError::RuntimeError {
+                    message: format!("Index must be a non-negative integer, got {}", n),
+                    token: None,
+                });
+            }
+            Ok(*n as usize)
+        } else {
+            Err(RuntimeError::RuntimeError {
+                message: "Index must be a number".to_string(),
+                token: None,
+            })
+        }
+    }
 }