Re: Help - Constructors - ASAP.

[tedennison@my-dejanews.com]

In article <EACHUS.98Jul30114523@spectre.mitre.org>,
  eachus@spectre.mitre.org (Robert I. Eachus) wrote:
> In article <6pi4jq$j73$1@nnrp1.dejanews.com> dennison@telepath.com writes:
>
>     There are two reasons for following the advice.  First is that Ada
> has a rule that inherited functions with a controlling result are
> abstract, so they must be overridden.  Yes, there are cases where
> constructor functions can be safely inherited from the parent, but
> this rule makes you think it through. Second is that when you do want
> a constructor which can return any type in the class, the right thing
> to do usually is to make it a classwide type.

But what happens in the situation where the client (perhaps a different
developer) wants to make a child class with fields that *must* be
initialized? That seems a quite reasonable thing to do. But now the
class-wide "constructor" isn't valid anymore. It can still be called for this
new child object, but will return a garbage value.

The only way I can see around this problem is to *also* declare a primitive
constructor, and have the body of the class-wide consructor redispatch to
that.

T.E.D.

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