Re: Unconstrained array aggregation..sq. peg into round hole?

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

Robert Eachus said:

"   I never understood why, if this useful and used feature was in Ada
83 and Ada 95, you have to go through all this semantic sugar to create
the ragged array type.  To keep novice users from trying it?"

it is not really a ragged array at all. If an implementation uses hidden
heap pointers (very few implementations do in this case, e.g. the old
Alsys technology, which sometimes uses hidden pointers, does not do so,
and the last time I used RR it warned of storage leaks here), then all
you have is an array of pointers, which is more easily declared
directly.

If the implementation allocates the maximum, fine, but that is not what
people call a ragged array!

THere is nothing odd about the syntax here, it is a natural combination
of features. If novices don't undrstand it, they certainly should not
be using it!

As for allowing directly the notion of array of unconstrained array, this
is no different from allowing e.g.

	X : String;

in the first place. Although this has definable semantics, it represents
a level of dynamic behavior that is inconsistent with the rest of the
Ada design (in particular, this would definitely require hidden heap
allocation, and probably only makes sense in a garbage collected regime).