I see what you mean -- many libraries provide conveniences like that
(like TagSoups `takeWhile (~== "</a>") tags' and so on). But that's
the inherent mismatch between a String-- a unicode literal --and
whatever else you want it to be, be it ASCII or bash or XML or
something else.. I think the answer to them all is to use TH (as
already suggested :-).
A similar issue is printf, which handles the errors at runtime (though
I think there's a TH solution already existing for that).
On Tue, Apr 24, 2012 at 10:58 AM, Yitzchak Gale
Markus Läll wrote:
What can go wrong when you use an overloaded string to be fromString'd into Text?
Here's an example:
The author of the xml-types package provides an IsString instance for XML names, so you can conveniently represent XML names as string literals in your source code.
But not every string is a valid XML name. If you mistype the literal, your program will still compile. It may even run for a while. But when someone uses your program in a way that causes that mistyped XML name literal to be resolved, your program will likely crash, unless you structured it in a way that allows that XML name literal to be wrapped in an appropriate exception handler in the IO monad.
-Yitz
-- Markus Läll