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From: "chris.danx" <spamoff.danx@ntlworld.com>
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Subject: Re: worth the hassle?
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"Stephen Leake" <stephen.a.leake.1@gsfc.nasa.gov> wrote in message
news:ulm8232w7.fsf@gsfc.nasa.gov...

> If Ada seems to be in your way when you want to do something, it's for
> a good reason!
>
> > What is a good way of getting the pointer to the list? 'access
> > doesn't work since list is constant, and I don't want to make the
> > parameter an access type since it's not convienant to declare lists
> > as aliased all the time.
>
> You can take the approach I did in SAL; don't store a pointer to
> the list in the iterators. That makes the iterators "unsafe", but more
> efficient.

They must be safe, so that approach isn't appropriate

> Or, you can take the approach that Grace.Lists does, and add a layer
> of indirection in the List_Type; then you _can_ get an access value to
> the list from an "in" parameter.

Do you mean something like

type a_list_type is ...

type list_type is record
   list : a_list_access;
end record;

or

type list_type is private;
...

private
   type a_list_type is ...

   type list_type is access a_list_type;

?

Where is the grace site?