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What is the purpose of Flask's context stacks?
...ing" example:
from werkzeug.wsgi import DispatcherMiddleware
from frontend_app import application as frontend
from backend_app import application as backend
application = DispatcherMiddleware(frontend, {
'/backend': backend
})
Notice that there are two completely different Flask applicat...
Can't find the PostgreSQL client library (libpq)
...
$ sudo su
$ env ARCHFLAGS="-arch x86_64" gem install pg
Building native extensions. This could take a while...
Successfully installed pg-0.11.0
1 gem installed
Installing ri documentation for pg-0.11.0...
Installing RDoc documentation for pg-0.11.0...
WORKE...
Replacing some characters in a string with another character
...zLMN and I want to replace all the occurrences of x , y , and z with _ .
5 Answers
...
The tilde operator in Python
...s operator.invert. To support this operator in your own class, give it an __invert__(self) method.
>>> import operator
>>> class Foo:
... def __invert__(self):
... print 'invert'
...
>>> x = Foo()
>>> operator.invert(x)
invert
>>> ~x
invert
Any ...
What does enumerate() mean?
What does for row_number, row in enumerate(cursor): do in Python?
5 Answers
5
...
TypeScript typed array usage
...
You have an error in your syntax here:
this._possessions = new Thing[100]();
This doesn't create an "array of things". To create an array of things, you can simply use the array literal expression:
this._possessions = [];
Of the array constructor if you want to se...
How to use timeit module
... you defined earlier during the interactive session by importing them from __main__ in the setup statement:
>>> def f(x):
... return x * x
...
>>> import timeit
>>> timeit.repeat("for x in range(100): f(x)", "from __main__ import f",
number=100000)...
How to use Boost in Visual Studio 2010
...boost (1.47.0 as of writing) into a directory of your choice (e.g. C:\boost_1_47_0).
Create a new empty project in Visual Studio.
Open the Property Manager and expand one of the configuration for the platform of your choice.
Select & right click Microsoft.Cpp.<Platform>.user, and select Pr...
Referring to the null object in Python
...t;> NoneType = type(None)
>>> id(None)
10748000
>>> my_none = NoneType()
>>> id(my_none)
10748000
>>> another_none = NoneType()
>>> id(another_none)
10748000
>>> def function_that_does_nothing(): pass
>>> return_value = function_that_...
Why aren't superclass __init__ methods automatically invoked?
Why did the Python designers decide that subclasses' __init__() methods don't automatically call the __init__() methods of their superclasses, as in some other languages? Is the Pythonic and recommended idiom really like the following?
...