Well, you can probably predict where my prejudice falls :-)  [clojure-like semantics]

Let’s see if @eriknw has a (tiebreaker?) opinion.

On Nov 7, 2013, at 3:21 PM, Matthew Rocklin <notifications@github.com> wrote:

> In toolz/dicttoolz/core.py:
> 
> > @@ -36,6 +36,9 @@ def merge_with(fn, *dicts):
> >      See Also:
> >          merge
> >      """
> > +    if len(dicts) == 0:
> Yup. That's the controversy. Normally this would return {}. This screws up curry though because merge_with(sum) actually works and so we don't close sum into the function. There are competing objectives. I'm not sure which way is best.
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