Re: Another Idea for Ada 20XX

["Marc A. Criley" <mcqada@earthlink.net>]

James Rogers wrote:
> 
> Take the situation of the NASA Mars probe that crashed because
> of an improper mixture of British and Metric distance units.
> 
> If the programming language used had provided the ability to
> perform unit analysis the mistake would have been caught by
> the compiler.

Actually, no it would not have been caught by the compiler.  While
working on an article several months ago I exchanged some emails with an
individual at Malin Space Science Systems, who knew exactly what had
happened there--which is why I'd contacted him.

The problem was that one program wrote a file of floating point numbers
representing values in British units, which was then read by a program
that expected floating point numbers representing metric units.  No unit
information accompanied the values in the file, they were just numbers.

Marc A. Criley
Senior Staff Engineer
Quadrus Corporation
www.quadruscorp.com