Ada Programming/Pragmas/Pack:3

Exact data representation It is important to realize that pragma Pack must not be used to specify the exact representation of a data type, but to help the compiler to improve the efficiency of the generated code. Pragma Pack vs. Convention C, portability issue? Adam Beneschan 2008-01-09 comp.lang.ada 3f729fc9-708f-49a5-82a5-b2d82038a47c@s12g2000prg.googlegroups.com http://groups.google.es/group/comp.lang.ada/msg/6698960624779ec7 2008-05-27 The compiler is free to ignore the pragma, therefore if a specific representation of a type is required, representation clauses should be used instead (record representation clauses, and/or attributes 'Size or 'Component_Size). Bit-wise operations Although in Ada 83 packed boolean arrays were used for bit-wise operations,Software Productivity Consortium (October 1995). Ada 95 Quality and Style Guide, "10 5 7 Packed Boolean Array Shifts" since Ada 95 modular types are more adequate for these operations.Software Productivity Consortium (October 1995). Ada 95 Quality and Style Guide, "10 6 3 Bit Operations on Modular Types" The argument may be weighed against the advantages of named Boolean array indexes such as Traffic_Lights'(Red => True, others => False), depending on use case.Pack