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What is the use of “assert” in Python?
...t True # nothing happens
>>> assert False
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AssertionError
Assertions can include an optional message, and you can disable them when running the interpreter.
To print a message if the assertion fails:
ass...
Change the image source on rollover using jQuery
...show/hide the rollover image when the onmousemove/onmouseout event happen. All my image names follow the same pattern, like this:
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Android SDK manager won't open
So I installed the android sdk for Windows:
29 Answers
29
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Create unique constraint with null columns
...or may not be useful. In extreme situations it might even help to maintain all three indexes (the two partial ones and a total on top).
Aside: I advise not to use mixed case identifiers in PostgreSQL.
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Decorators with parameters?
...tion that will take a function and return another function. So it should really return a normal decorator. A bit confusing, right? What I mean is:
def decorator_factory(argument):
def decorator(function):
def wrapper(*args, **kwargs):
funny_stuff()
something_with...
How to make a Java Generic method static?
...urn value always introduce (declare) a new generic type variable.
Additionally, type variables between types (ArrayUtils) and static methods (appendToArray) never interfere with each other.
So, what does this mean:
In my answer <E> would hide the E from ArrayUtils<E> if the method woul...
What can you do in MSIL that you cannot do in C# or VB.NET? [closed]
All code written in .NET languages compiles to MSIL, but are there specific tasks / operations that you can do only using MSIL directly?
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No compiler is provided in this environment. Perhaps you are running on a JRE rather than a JDK?
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On your Eclipse IDE, go into Window > Preferences > Java > Installed JREs > and check your installed JREs. You should have an entry with a JDK there.
Select the Execution Env as show below. Click OK
Then Right-Click on your Project -> Maven -> Update Project
Additionally, yo...
Most efficient way to determine if a Lua table is empty (contains no entries)?
...olution though, and I honestly can't assume that my solution is faster overall.
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Ways to implement data versioning in MongoDB
... approach would be to store diffs. Because the display of these diffs is really a special action, I would put the diffs in a different "history" collection.
I would use the different collection to save memory space. You generally don't want a full history for a simple query. So by keeping the histo...