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: Send--binary (Object) ------------------------------------------------------------------------------ Syntax <object>:<message>[(<argument list>)] Type Object Operands <object> is the name of the object that is to receive the message. <message> is the name of a method or instance variable. <argument list> is a list of parameters that are passed to the specified message. The parentheses surrounding the argument list are optional if no parameters are supplied in the message send. By convention, however, parentheses distinguish a message send with no parameters from an access to an exported instance variable. Description Each class defines a set of operations that can be performed on objects of that class. Perform these operations by sending a message to the object using the send operator (:). When a message is sent to an object, the system examines the message. If the object is of a class that defines an operation for that message, the system automatically invokes a method to perform the operation on the specified object. If the class does not define a method for the specified message, a runtime error occurs. Executing a message send produces a return value, much like a function call. The return value varies depending on the operation performed. Examples . In this example, myBrowse is the name of a variable that contains a TBrowse object reference. pageUp() is a method that specifies the operation to be performed. The available operations and corresponding methods vary depending on the class of the object. The Error, Get, TBColumn, and TBrowse classes are documented in this chapter. myBrowse:pageUp() . This example forces the checkbox state to true (.T.): myCheck : Select (.T.)
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