On Tue, 04 Jun 2013 14:53:29 +0300, Carlos Nepomuceno wrote:
> That's exactly the same!
>>>>dict(**{a:0,b:1})=={a:0,b:1}
> True
Of course it is. Isn't that what you wanted?
It's also a waste of time, because you create a dict literal using {},
then unpack it into keyword arguments, then call dict() to create a new
dict with the same content. Rather like doing this:
n = int(str(42))
only even more expensive.
> Are there any benefits from using dict() instead of {}?
Of course there are. {} can be used for creating dict literals, which
means you are limited to key/values that you explicitly include. dict(),
on the other hand, has a rich set of constructor APIs:
py> help(dict)
Help on class dict in module builtins:
class dict(object)
| dict() -> new empty dictionary
| dict(mapping) -> new dictionary initialized from a mapping object's
| (key, value) pairs
| dict(iterable) -> new dictionary initialized as if via:
| d = {}
| for k, v in iterable:
| d[k] = v
| dict(**kwargs) -> new dictionary initialized with the name=value pairs
| in the keyword argument list. For example: dict(one=1, two=2)
py> dict(zip('abcd', range(4)), x=23, y=42, z=999)
{'a': 0, 'c': 2, 'b': 1, 'd': 3, 'y': 42, 'x': 23, 'z': 999}
Try doing that with {} alone!
--
Steven
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