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What is “lifting” in Scala?
...Stream[A]]. This can be converted to the monad transformer StreamT[IO, A]. Now you may wish to "lift" some other value an IO[B] perhaps to that it is also a StreamT. You could either write this:
StreamT.fromStream(iob map (b => Stream(b)))
Or this:
iob.liftM[StreamT]
this begs the question:...
Instance variables vs. class variables in Python
...else it's code created by an aberrant programmer wanting to show off they know some obscure corner of Python programming.
Alex mentions in his reply that access will be (a little bit) faster due to one less level of lookup... let me further clarify for those who don't know about how this works yet....
Python strptime() and timezones?
... noting this has been updated as of version 3.2 and the same documentation now also states the following:
When the %z directive is provided to the strptime() method, an aware datetime object will be produced. The tzinfo of the result will be set to a timezone instance.
Note that this doesn't w...
What's the idiomatic syntax for prepending to a short python list?
...icient, because in Python, a list is an array of pointers, and Python must now take every pointer in the list and move it down by one to insert the pointer to your object in the first slot, so this is really only efficient for rather short lists, as you ask.
Here's a snippet from the CPython source...
How do you switch pages in Xamarin.Forms?
...et slightly not MVVM pure solution. That is because the Page(View) should know nothing about the ViewModel and vice versa. Here is a great example of this violation:
// C# version
public partial class MyPage : ContentPage
{
public MyPage()
{
InitializeComponent();
// Violati...
Foreign Key to non-primary key
... key, otherwise, data-garbage is the result sooner rather than later...
Now what you can do in this case (short of rewritting the entire application) is inserting a CHECK-constraint, with a scalar function checking the presence of the key:
IF EXISTS (SELECT * FROM sys.check_constraints WHERE ob...
Best way to define error codes/strings in Java?
...g or whatever*/ id();
}
public interface IMessage {
ICode code();
}
Now you can define any number of enums which provide me
How to determine the encoding of text?
I received some text that is encoded, but I don't know what charset was used. Is there a way to determine the encoding of a text file using Python? How can I detect the encoding/codepage of a text file deals with C#.
...
tomcat - CATALINA_BASE and CATALINA_HOME variables
...
I can't say I know the best practice, but here's my perspective.
Are you using these variables for anything?
Personally, I haven't needed to change neither, on Linux nor Windows, in environments varying from development to production. Unl...
How to “perfectly” override a dict?
...tween Python 2 and 3, create a singleton (_RaiseKeyError) to make sure we know if we actually get an argument to dict.pop, and create a function to ensure our string keys are lowercase:
from itertools import chain
try: # Python 2
str_base = basestring
items = 'iteritems'
except...