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What does “Splats” mean in the CoffeeScript tutorial?
...s object in such a way that the splatted argument becomes an array of all "extra" arguments. The most trivial example is
(args...) ->
In this case, args will simply be an array copy of arguments. Splatted arguments can come either before, after, or between standard arguments:
(first, rest...)...
Python unittest - opposite of assertRaises?
...the correct solution in fact. The solution proposed by user9876 is conceptually flawed: if you test for the non-raising of say ValueError, but ValueError is instead raised, your test must exit with a failure condition, not an error one. On the other hand, if in running the same code you would raise ...
What is a clean, pythonic way to have multiple constructors in Python?
...
Actually None is much better for "magic" values:
class Cheese():
def __init__(self, num_holes = None):
if num_holes is None:
...
Now if you want complete freedom of adding more parameters:
class Cheese...
What is the difference between OpenID and SAML?
...rther expands this to make it possible to obtain the identity without this extra step involving the call from the application to the identity provider. The idea is based on the fact that OpenID Connect providers in fact issue two tokens, the access_token, the very same one OAuth2.0 issues and the ne...
How to profile a bash shell script slow startup?
... do better -- using \D{...} in PS4 allows completely arbitrary time format strings to be expanded without the performance overhead of launching date as a subprocess.
– Charles Duffy
Jul 18 '13 at 21:35
...
SQL - find records from one table which don't exist in another
... Phone_book USING (id)
WHERE Phone_book.id IS NULL
This will return the extra id-s that are missing in your Phone_book table.
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Is the Scala 2.8 collections library a case of “the longest suicide note in history”? [closed]
...mutable.BitSet = BitSet(2, 3, 4)
scala> val displayed = bits map { _.toString + "!" }
displayed: scala.collection.immutable.Set[java.lang.String] = Set(1!, 2!, 3!)
See how you always get the best possible type? If you map Ints to Ints you get again a BitSet, but if you map Ints to Strings, you...
Fastest way to get the first object from a queryset in django?
...eturn None if there aren't any. There are lots of ways to do this which all work. But I'm wondering which is the most performant.
...
How do you write tests for the argparse portion of a python module? [closed]
...turn parser.parse_args(args)
Then in your main function you should just call it with:
parser = parse_args(sys.argv[1:])
(where the first element of sys.argv that represents the script name is removed to not send it as an additional switch during CLI operation.)
In your tests, you can then call...
What is the difference between join and merge in Pandas?
...
pandas.merge() is the underlying function used for all merge/join behavior.
DataFrames provide the pandas.DataFrame.merge() and pandas.DataFrame.join() methods as a convenient way to access the capabilities of pandas.merge(). For example, df1.merge(right=df2, ...) is equiva...