From the wiki:

Cor must be better than what you can get in Python 3, Ruby, Swift, and so on.

That would be really nice (and I do appreciate the effort put into this), but some reasons I think it falls short of being truly better:

1. No autoboxing. What if you'd used a plain hash instead of Hash::Ordered? In Python/Ruby e.g. it's nice that when dealing with hashes and arrays you can call methods on them so there isn't the kind of mental switching between OO and procedural that we must do in Perl.

2. Lack of uniformity between built in containers and user defined ones. In the Hash::Ordered docs there is this snippet:

$oh->add( 'a', 5 );           # like $oh{a} += 5
$oh->concat( 'a', 'hello' );  # like $oh{a} .= 'hello'
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I don't get the impression Cor would actually let both of those work. Whereas in Python this would look like:

>>> h = {'a' : 1}
>>> h['a'] += 2
>>> h
{'a': 3}
>>>
>>> from collections import OrderedDict
>>> oh = OrderedDict(h)
>>> oh
OrderedDict([('a', 3)])
>>> oh['a'] += 2
>>> oh
OrderedDict([('a', 5)])
>>> oh['b'] = 'hello'
>>> oh['b'] += ' world'
>>> oh
OrderedDict([('a', 5), ('b', 'hello world')])
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3. We're still conflating interfaces and implementations (surely we can do better?). I'd really wish class definitions to be more self documenting so I can first get an overview of what it does, and then focus on the "how". FWIW, I did a proof of concept of what this could be like. So e.g. the first thing you see is the "what" which can be more rich than just a list of methods (contracts in fact).