This chapter defines the facilities for dealing with errors or other exceptional situations that arise during program execution. Such a situation is called an exception. To raise an exception is to abandon normal program execution so as to draw attention to the fact that the corresponding situation has arisen. Executing some actions, in response to the arising of an exception, is called handling the exception.
An exception declaration declares a name for an exception. An exception can be raised by a raise statement, or it can be raised by another statement or operation that propagates the exception. When an exception arises, control can be transferred to a user-provided exception handler at the end of a block statement or at the end of the body of a subprogram, package, or task unit.
References: block statement, error situation, exception handler, name, package body, propagation of an exception, and 11.4.2, raise statement, subprogram body, task body.