Safe Haskell default

[Daniel Fischer]

On Wednesday 26 October 2011, 19:50:09, Johan Tibell wrote:
> On Wed, Oct 26, 2011 at 9:04 AM, Thomas Schilling
> 
> <nominolo at googlemail.com>wrote:
> > I while ago I saw a commit to Safe Haskell changing modules from
> > default Unsafe to default Safe.
> > 
> > This seems wrong to me (and Duncan agreed on IRC) -- in security the
> > usual advice is to use white listing instead of black listing.  The
> > reasoning is that if you forget to white list something safe, it
> > causes some inconvenience; but if you forget to blacklist something
> > unsafe it's a security flaw.
> > 
> > Is there some more documentation on why this decision was made?  Was
> > it just to avoid adding a pragma to every module?
> 
> The other way around force those who don't use Safe Haskell to still
> deal with it. It should be an opt-in language feature, just like every
> other language feature.

I don't understand this. If I don't use Safe Haskell, the compiler should 
ignore all the Safe/Trustworthy/Unsafe pragmas no matter what's the 
default.
Only if I explicitly choose to use Safe Haskell by putting an -XSafeHaskell 
on the command line should it care, and then I'd expect modules without 
info to be deemed unsafe by default.