Table 3.1. Variable Modifiers
| package | The variable can only be accessed within the package where it is defined. See Access Modifiers. |
| protected | The variable can be accessed from the package where it is defined and from subclasses of the class where it is defined. See Access Modifiers. |
| public | The variable can be accessed anywhere. See Access Modifiers. |
| public-read | The var can be read anywhere. See Access Modifiers. |
| public-init | The var can be initialized or read anywhere. Where initialized means set (but not bound) in an object literal. See Access Modifiers. |
While syntactically optional, an initializingExpression is required with def.
When bind is specified in the initializingExpression the variable is kept updated to the value of the expression. When with inverse is specified, the expression must be a simple variable reference and that variable is kept updated when the variable being declared is changed. See the Binding chapter for details.