Readline read_history and write_history addition

Yitzchak Gale gale at
Mon Feb 4 09:06:22 EST 2008

Simon Marlow wrote:
> Here's my (slightly provocative) take on this: a MonadIO instance is not a
> complete wrapper around the IO monad, because it doesn't provide catch.

That's true.

> It is not the responsibility of a library that provides IO functions to
> account for defficient wrappers of IO with no way to catch exceptions.  The
> problem is in the IO wrapper, not the library that throws exceptions.

Makes sense.

> However, I do agree that exceptions should generally be used for
> exceptional conditions, rather than for general control-flow.  This is an
> example of a *good* reason to avoid an exception: because to use an
> exception for a non-exceptional condition is poor style.

That is also my opinion. Some people have disagreed.
So this should be the focus of the decision then.


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