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From: Robert Dewar <robert_dewar@my-deja.com>
Subject: Re: disjoint ranges ?
Date: 2000/10/18
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In article <39EBB984.F2F8905F@ix.netcom.com>,
  Lao Xiao Hai <laoxhai@ix.netcom.com> wrote:
> So, making a feature more powerful might be something such as
being
> able to overload the "in" membership test.   For some reason,
this
> operator is not really a first class operator in Ada.

For very good reasons! The right operand of IN is not a value,
but a range. If you want to start making discrete ranges
first class values, you have suddenly taken (one of many)
avaliable trains to the land-of-increased-complexity.

It is easy to throw out an idea like this casually, but if
you even start to try to think what all the effects would
be on the existing semantics, you will find that it is far
harder than you think. Language design is like skiing, it
looks much easier than it is, and it is only when you actually
start doing it, that you find out it is more complex :-)


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