Re: Question for the folks who designed Ada95

[Robert Dewar <robert_dewar@my-dejanews.com>]

In article <3725C49E.8106A44B@aasaa.ofe.org>,
  David Starner <dstarner98@aasaa.ofe.org> wrote:
> But that was a deliberate choice. IIRC, Ada 83 depended
> on ASCII which supplied [], so they could have gone with
> brackets.

This is bad history! The requirement for the character set
in Ada 83 was much more strenuous, it included
compatibility with current common usage, which included
EBCDIC (e.g. IBM keypunches) which did NOT provide the []
characters.

But even now there are those who do not like at all to
create referential non-transparency between arrays and
functions, since they regard these as two alternative
low level implementations of the abstract mathematical
concept of a function or map.

In other words:

  a(5)

is a reference to a mapping, and you want the range value
given the domain value 5. Whether this is implemented by
an array or a function is an implementation detail that
should not affect the syntactic form of reference.

I personally like the [] since I was immersed in the Algol
world so long, and I particularly liked this usage in
A68, but the above argument is definitely a legitimate one!



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