Re: [Q]: Unchecked conversion

[dewar@merv.cs.nyu.edu (Robert Dewar)]

Jonas asks about conversion of unconstrained array types.

First, the solution with address clauses is of course for CONSTRAINED
array types (since all objects are constrained), and you could perfectly
well use unchecked conversion, or, as I suggested unchecked conversion
of pointers (since there is no need to copy the data) and if all array
types are constrained, then that should be portable.

Note that the solution with address clauses is definitely wrong for
Ada 83 (i.e. erroneous). The effect is implementation dependent in
Ada 95. In practice it will probably work, but I still think that
unchecked conversions of poitners to constrained array subtypes is
a much cleaner approach.

The use of address clauses in this way is really an *ab*use!