Debugging haskell

D. Tweed tweed@compsci.bristol.ac.uk
Mon, 24 Feb 2003 15:41:12 +0000 (GMT)


On Mon, 24 Feb 2003, Andrew Moran wrote:

> 
> Dave Tweed wrote:
> 
> > If you discard `compliation preventing, very very quick to solve' bugs
> > (e.g., missing semi-colons in C++, silly typecheck errors in Haskell) I
> > find that the ratio between source code bugs and algorithm bugs is maybe
> > 1:5. This means that whilst I find Haskell a great deal easier to write
> > correctly than C++, there's not that much difference between debugging
> > times for Haskell and C++ because the algorithm level bugs dominate.
> 
> In my experience, the number of algorithm bugs is usually about the same, 
> regardless of which language you're using.  And simple source code bugs are 
> no real problem in any language.

I think I was a bit unclear: I agree that no of algorithm bugs is
essentially independent of programming language. What I was trying to say
was that whilst there's much less debugging time on `non-trivial' source
code bugs (by which I mean things like, say, having a nested if which
doesn't work the way you think it does) is much less in Haskell, those are
a relatively small proportion of the bugs. Consequently there's not a big
disparity between the time I spend debugging Haskell and time spent
debugging C++ because language independent bugs are the bottleneck.

So in my case I couldn't justify using Haskell on the grounds of reduced
debugging time. (I could justify it on lots of other grounds of course...)

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