Proposal: Debug.Trace.traceWith

[David Feuer]

On Feb 10, 2018 11:53 AM, "Kris Nuttycombe" <kris.nuttycombe at gmail.com>
wrote:


On Fri, Feb 9, 2018 at 7:07 PM, David Feuer <david.feuer at gmail.com> wrote:

> Other another bike-shed color:
>
> traceWith :: (a -> String) -> a -> a
> traceWith f a = trace (f a) a
>
> traceShowWith :: Show b => (a -> b) -> a -> a
> traceShowWith f = traceWith (show . f)
>

Is there some situation where the `Show String` instance wouldn't be in
scope? If `b` is `String` it works out just fine, so the first definition
you gave here seems superfluous.


If the strings have non-ASCII characters, show will mangle them.
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