Object-oriented Software in Ada 95

376 Appendix B
Tasking_Error
Raised when an error occurs in a task.
B.7.2I/O exceptions
Exception
Data_Error
End_Error
Mode_Error
Name_Error
Status_Error
Use_Error
B.8 Ada 95, the structure
Explanation
Raised when a get on a numeric object finds the input is
not a valid value of this numeric type.
Raised when an attempt is made to read past the end of
the file.
Raised when an inappropriate operation is attempted on
a file.
Raised if the name used in an open call does not match
a file in the external environment.
Raised when an operation is attempted on a file that has
not been opened or created.
Raised if the attempted operation is not possible on the
external file.
The Ada 95 programming language is split into two distinct sections: a core language that must be implemented
and a series of annexes that may or may not be implemented. The annexes extend the language into problem
specific areas. The annexes to the language are:
Annex Name Contents of annex:
C System programming The provision of features that will allow the
interfacing of an Ada program to external
environments. For example, the interfacing of
Ada code to a peripheral device or to components
of the operating system interface.
D Real time systems The provision of features that will allow the
control of real-time processes.
E Distributed systems The provision of features that will allow a system
to extend beyond a single address space in a
single machine.
F Information systems The provision of features that will allow an Ada
program to communicate with programs or
systems written in C or COBOL.
G Numerics The provision of features that will allow the
construction of numerically intense applications
H Safety and security Restrictions to the language to minimize
insecurities and areas in which compromises to
validation and verification would be made.
Note:
The annexes rarely extend the syntax of the language; rather they provide extra packages to enable the
particular area to be performed.
B.9 Sources of information
B.8.1Copies of the Ada 95 compiler
The main internet site for copies of the GNAT Ada 95 compiler is cs.nyu.edu. The latest version of the
compiler for a multitude of machines is held in the directory pub/gnat.
© M A Smith - May not be reproduced without permission