[Python-ideas] Adding "+" and "+=" operators to dict

[Stephen J. Turnbull]

Rob Cliffe writes:

 > There are many features of the languages where decisions have had
 > to be made one way or another.  Once the decision is made, it's
 > unfair to say the semantics are muddy because they could have been
 > different.

The decision hasn't been made yet.  At this point, it *is* fair to
argue that users will be confused about the semantics of the syntax
when they encounter it, and that looking it up is a burden.  Many
times we see professional Python programmers on these lists say "I
always have to look that one up".

Whether that argument should win or not, is the question.  It has been
decided both ways in the past.  Here the burden is not so great, but
IMO the benefit is even less (to me net negative, as I would use, and
often define, appropriate methods, not the syntax).

YMMV, I just wanted to lay out the case for multiple interpretations
being confusing, as I understand it.  And missed two (Greg Ewing
suggested non-numerical conflicts, and Steven reported a suggestion of
multiple values inserted in container).