Re: XML DOM Binding for Ada 95 - matter of style

[Marin David Condic <nobody@noplace.com>]

You can use type extension without adding anything "dynamic" to a 
system. Its a perfectly good way of adding things to a record type that 
already exists. The "dynamic" part happens only if you are using 
dispatching in some way. AFAIK, you can add subprograms with a type 
extension that can be determined statically. They just can't be used as 
class-wide operations.

People have different styles. I don't object to discriminated records 
totally - it can be made to work and in some cases, it is a reasonable 
reflection of a given design. However, since Ada got tagged records and 
is capable of making classes, I think it has diminished the need for 
things like discriminated records because tagged records are so much 
more powerful and they address the same need. In the case of the XML 
DOM, I thought they were a more natural reflection of the design. You 
may have done it differently and it may work fine, but I don't think it 
lines up well with the intent of the DOM spec - at least not as well as 
tagged records would have.


MDC



Matthew Heaney wrote:
> 
> 
> The type extension exists in order to implement the dynamically bound
> operation.
> 


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Marin David Condic
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