4.3.2. Class Library Notes

The chapters that follow describe the classes and other objects that Rexx provides and their available methods. Rexx provides the objects listed in these sections and they are generally available through environment symbols.

Notes:

In the method descriptions in the chapters that follow, methods that return a result begin with the word "returns".
For [] and []= methods, the syntax diagrams include the index or indexes within the brackets. These diagrams are intended to show how you can use these methods. For example, to set the element (2, 3) of a multi-dimensional Array named matrix to 0, you would typically use the syntax:
```
matrix[2, 3] = 0
```
rather than:
```
matrix~"[]="(0, 2, 3)
```
even though the latter is valid and equivalent. For more information, see Section 1.11.4, “Message Terms” and Section 1.12.6, “Message Instructions”.
When the argument of a method must be a specific kind of object (such as array, class, method, or string) the variable you specify must be of the same class as the required object or be able to produce an object of the required kind in response to a conversion message. In particular, subclasses are acceptable in place of superclasses (unless overridden in a way that changes superclass behavior), because they inherit a suitable conversion method from their Rexx superclass.
The isA method of the Object class can perform this validation.