On Tue, Nov 14, 2006 at 12:08:07PM +0000, Jon Fairbairn wrote:
> >[..]
> > My last impression is that instead of using -xc it is better to write
> > programs in a debug-friendly style. For example, let g x must
> > return (Just _), but the programmer is not 100% sure that g x is free
> > of bugs. Then, instead of
> > f x = h $ fromJust $ g x
> > one needs too write
> >
> > f x = case g x
> > of
> > Just y -> h y
> > _ -> error $ concat
> > ["Foo.f ", shows x "\n:\nImpossible happened:\n",
> > "g ", shows x " = Nothing.\n"
> > ]
>
> wouldn't
>
> f x = maybe mistake h (g x)
>
> where mistake = error $ ("Foo.f "++).
> shows x.
> (":\nThis shouldn't happen:\ng "++).
> shows x
> $ " = Nothing.\n"
>
> be slightly tidier?
1) I do not see why the latter is tidier. It uses two extra functions.
2) By "needs to write" I meant "needs to write something like".
-----------------
Serge Mechveliani
[EMAIL PROTECTED]
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