Now read the above but instead of “it’s not super obvious what

  d1 | d2

should be because losing information/desirable properties/weird errors”, read “it’s not super obvious what

  {**d1, **d2}

should be because losing information/desirable properties/weird errors”.

Except I guess one could throw in something about TOOWTDI too.

I actually think it is obvious what a dictionary merge should do (overwrite keys on the left with keys on the right), but this is besides the point because it's already been determined for

    {**d1, **d2}

In other words, there are no new semantics to discuss here. I'm just saying the two syntaxes should be equivalent.