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From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Dynamic type system for Ada
Date: Tue, 24 Jan 2017 21:41:43 -0800
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Date: 2017-01-24T21:41:43-08:00
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Victor Porton <porton@narod.ru> writes:
> Due to pure curiosity, I ask: Has anybody developed a dynamic type system 
> for Ada?

That's not so easy.  You have to be able to wrap an arbitrary Ada object
in another object, along with a tag saying what the Ada type is.  That
means you have to be able to encode every Ada type into a tag, and types
can be quite complicated (maybe arbitrary tree structures even).  Also
the compiler might or might not have a way of telling the runtime what
type something has.

There is something like this in Haskell called Data.Dynamic, but they
had to add special features to the compiler and runtime to support it.