Ordered dict by default

[MRAB]

bearophileHUGS at lycos.com wrote:
> Cameron Simpson:
> 
>> increases the unrealised assumptions about mappings in general
>> which a newbie may acquire, causing them pain/complaint later with
>> other mappings<
> 
> This is wrong in several different ways.
> 
>> I would much rather keep dictionaries as performant as possible, as
>> a bare mapping, and add an odict for when order matters.
> 
> In Python 3 strings are all unicode, integral numbers are all 
> multiprecision, chars in Python 2.x+ are strings, lists are arrays 
> that can grow dynamically, and so on because the Purpose of Python 
> isn't to be as fast as possible, but to be first of all flexible, 
> safe, easy, not but-prone, even if other solution or older versions 
> were faster. Ruby shares almost same purposes.
> 
> I presume Ruby wants to become a bit higher level than Python,
> because it now has a more flexible built-in. But even in a language
> designed to run way faster than Python, like D, I think the right
> thing for built-ins is to be as flexible&easy as possible, so they
> are good enough in as many situations as possible, where performance
> isn't the most important thing, and to put the more specialized and
> faster versions into external libs. Making the built-ins be as
> optimized as possible (but limited too) looks like premature
> optimization to me, and in a language like Python premature
> optimization looks even more silly than usual.
> 
You'll be wanting ordered sets next! :-)