[Python-ideas] Dict joining using + and +=

[Greg Ewing]

Serhiy Storchaka wrote:
> I do not understand why we discuss a new syntax for dict merging if we 
> already have a syntax for dict merging: {**d1, **d2} (which works with 
> *all* mappings).

But that always returns a dict. A '+' operator could be implemented
by other mapping types to return a mapping of the same type.

-- 
Greg