Teaching Ada types

["J-P. Rosen" <rosen@adalog.fr>]

(was: Re: Beginning Ada Programming, by Andrew T. Shvets (2020))

Here is how I explain the Ada approach:

Whatever the language, when you need to represent data, it is important
to choose an appropriate type. This involves two steps:
1) Analyze your problem to determine the requirements (range f.e.) on
your type
2) Make a representation choice, i.e. choose a machine type that covers
the requirements of 1)

Ada saves you step 2), by allowing you to express your needs directly,
and leaving the choice of representation to the compiler.

The trouble is that other languages offer only machine types (for basic
types). Therefore, most people tend to think directly in terms of
machine types and skip step 1.

--------------------------------------------------------
Of course, this assumes that you teach how to create software, and not
just a language. Some times ago, a little niece of mine started a
software school. I was especially interested in how design was taught!
Well, the school taught the syntax of C, and then gave programming
exercises. I asked: "but how did they teach you how to go from a problem
statement to its solution?" She didn't even understand what I was
talking about. Sigh...

-- 
J-P. Rosen
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