[Haskell] Haskell as a disruptive technology?

[Malcolm Wallace]

Dusan Kolar <kolar at fit.vutbr.cz> wrote:

> > Yes.  Safety critical systems, encompassing everything from avionics
> > to railway signalling equipment, to medical devices.  These markets
> > are relatively small / low-volume, with needs for high assurance,
> > and better development times.
> >   
> Well, the market is growing and not that small. ;-) Think of mobile 
> phones and cars, for instance, they are "full" of embedded computers.

The embedded computation market is certainly huge (about 10x the size of
the PC market), but how many of those systems are actually safety
critical?  Mobile phones certainly are not.  A safety critical system is
one whose failure could directly lead to loss of life, e.g. gas turbine
engine controller on an Airbus.

> >   * Analysing and guaranteeing performance characteristics (time,
> >     memory) is something we still can't do well with Haskell.  
>
> Well, is it a problem to make GC a deterministic task or there is a 
> problem that a program may run out of memory unpredictably? Can you be
> more explicit, or link to some article?

The problem goes much further than amortising the cost of GC.  With lazy
evaluation, in general we do not even know the complexity class of space
usage (constant, linear, exponential) for any given program of moderate
size without doing some empirical measurement or profiling.  There have
been a few attempts at formal analysis in this field (Pareto and Hughes,
Hammond and Michaelson) but nothing is yet truly comprehensive.

Regards,
    Malcolm