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[Python-ideas] Preserving **kwargs order

Terry Reedy tjreedy at udel.edu
Fri Apr 4 10:54:07 CEST 2014 
This proposal strikes me as conceptually disordered. A set is not 
ordered. An ordered set would be a sequence, and if you want a sequence, 
the best thing is to use a sequence object.  A dict is a set of 
key,value pairs. If you want an ordered sequence of key, value pairs, 
use a sequence. OrderedDicts were added for situations where that is not 
possible because a pre-existing api requires a mapping object, even 
though you might prefer to use a sequence.

Passing a sequence of key,value pairs is a case that requires a mapping. 
If a function attends to the order of key,value pairs it receives, it 
should receive a sequence of such.

**kwds in a call is a substitute for writing out unordered key=value 
specifications. The function may or may not have **kargs in its 
signature and if it does, the kargs received may or may not be equal to 
the kwds passed.

-- 
Terry Jan Reedy
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