     }
 
     /// The label of the argument.
-    public let label: String?
+    public var label: String?
 
     /// The binding operator of the argument.
-    public let bindingOp: Operator?
+    public var bindingOp: Operator?
 
     /// The value of the argument.
-    public let value: Node
+    public var value: Node
 
     // MARK: Annotations
 

    }

    /// The condition of the expression.
    public let condition: Node

    /// The block of statements to execute if the condition is statisfied.
    public let thenBlock: Node

    /// The block of statements to execute if the condition isn't statisfied.
    public let elseBlock: Node?

    // MARK: Annotations


    }

    /// The owner.
    public var owner: Node?

    /// The ownee.
    public var ownee: Ident

    // MARK: Annotations

