[Python-ideas] Preserving **kwargs order

[David Mertz]

I confess that after reading this thread, and a number of related past
ones, I'm still not certain exactly what problem all of this is needed to
solve.  ISTM that if one has a special function calling requirement to pass
in an ordered collection of key/value pairs, one can already just use a
special and available call signature for your function:

  def myfunc(a, b, *keyvals):
      od = OrderedDict(keyvals)
      # ... do other stuff

Call this like:

  value = myfunc(foo, bar, ('a',1), ('z',2), ('b',3))

Yes, it's a slightly special form of the calling convention, but it does
something slightly special with its key/val-like arguments, so that seems
like a reasonable tradeoff.  The solution is purely local to the writer of
the function who needs this.

Even if you have an existing OrderedDict that you want to pass in, you can
use that like:

  value = myfunc(foo, bar, *myOD.items())

Of course, if you want to be picky, you could stick in a check at the top
of your function definition:

  assert all(isinstance(x, tuple) and len(x)==2 for x in keyvals)





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