Changing the Search Order for Methods

When composing a message, you can change the default search order for methods by doing both of the following:

Making the receiver object the sender object. (You usually do this by specifying the special variable SELF. SELF holds the value of the object in which a method is running. You can use SELF to run another method in an object where a method is already running or pass references about an object to the methods of other objects.)
Specifying a colon and a class symbol after the message name. The class symbol identifies the class object to use as the starting point for the search. This class object must be:
- A direct superclass of the class that defines the active method
- The object's own class, if you used SETMETHOD to define the active method
  The class symbol is usually the special variable SUPER, but it can be any environment symbol or variable name whose value is a valid class.
In A Sample Program Using Directives, an Account subclass of the Object superclass is created. It defines a TYPE method for Account, and creates the Savings subclass of Account. The example defines a TYPE method for the Savings subclass, as follows:
```
::class Savings subclass Account

  ::method 'TYPE'
    return "a savings account"
```
To change the search order so REXX searches for TYPE in the Account rather than Savings subclass, enter this instead:
```
  ::method 'TYPE'
    return self~type:super '(savings)'
```
When you create an asav instance of the Savings subclass and send a TYPE message to asav:
```
say asav~type
```
REXX displays:
```
an account
```
rather than:
```
a savings account
```
because REXX searches for TYPE in the Account class first.

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