Programmer's Reference

Message and DirectedMessage

The concept of a Message class is briefly discussed in the Blue Book, but no details are provided about its protocol. CLDT defines both a Message class and a DirectedMessage class. Both are used in error handling and to support communication between the virtual machine and the rest of the system. A Message represents a Smalltalk message. It supports the basic accessors arguments, arguments:, selector, and selector:. A DirectedMessage is a Message that also knows about its receiver. It supports the basic accessors plus receiver, receiver:, and send.

Porting tip:
In Objectworks\Smalltalk a DirectedMessage is called a MessageSend. Smalltalk/V has no equivalent of Message, but has a class Message that is equivalent to DirectedMessage. Messages are created using the class message new. DirectedMessages in IBM Smalltalk can be created by sending the class messages new and selector:arguments:receiver:.


[ Top of Page | Previous Page | Next Page | Table of Contents | Index ]