Re: why are these unknown identifiers?

[csus.edu!wupost!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!caen!uv aarpa!software.org!smithd@ucdavis.ucdavis.edu (Doug Smith)]

In article <9109101616.aa26718@PARIS.ICS.UCI.EDU> jduarte@liege.ICS.UCI.EDU (Jo
se Duarte) writes:
> -----------------------------------------
> package X is
> 	type DIRECTIONS is (UP,DOWN,LEFT,RIGHT);
> end X;
> -----------------------------------------
> with X;
> package Y is
> 	subtype DIRECTIONS is X.DIRECTIONS;

replace the subtype declaration with a derived type:
    type Directions is new X.Directions;
 
> end Y;
> -----------------------------------------

remove extraneous with of Text_IO.

> with Y;
> procedure BUG is
> 
> V1 : Y.Directions := Y.UP;    -- Y.UP is unknown
> V2 : Y.Directions := Y.DOWN;  -- Y.DOWN is unknown
> 
> begin
>   null;
> end BUG;
> 
> Can someone tell me why "Y.UP" and "Y.DOWN" are unknown identifiers
> within the procedure BUG? I have to "with X" and then assign X.UP
> and X.DOWN to V1 and V2 in order to compile this. Why is this the case?
> Is this an Ada pecularity or a compiler bug?
> 
> 
> Thanks!
> JOSE DUARTE

Make the above change from subtype to derived type to
accomplish what you were trying (I didn't see any reason
to with Text_IO).  Of course, you will find other differences
which you may not like, such as the need for explicit
type conversions.

Now you can study the differences between subtypes and
derived types (I have never been able to do better than
the LRM, and will let others "explain" the differences).