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When is “i += x” different from “i = i + x” in Python?
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This depends entirely on the object i.
+= calls the __iadd__ method (if it exists -- falling back on __add__ if it doesn't exist) whereas + calls the __add__ method1 or the __radd__ method in a few cases2.
From an API perspective, __iadd__ is supposed to be used fo...
What's the best way to distribute Java applications? [closed]
...use a jar. This assumes that the user has the the correct java version installed, otherwise the user will get "class-file format version" exceptions. This is fine for internal distribution inside a company.
Use launch4j and an installer like NSIS. This gives you a lot more control, although the user...
Assignment inside lambda expression in Python
I have a list of objects and I want to remove all objects that are empty except for one, using filter and a lambda expression.
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UDP vs TCP, how much faster is it? [closed]
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There are actually many cases where TCP is actually faster than UDP. See my answer below.
– Robert S. Barnes
Feb 15 '11 at 6:53
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JavaScript: What are .extend and .prototype used for?
...ate ).lol() // alert message
In the snippet above, I define a method for all Date objects ( already existing ones and all new ones ).
extend is usually a high level function that copies the prototype of a new subclass that you want to extend from the base class.
So you can do something like:
e...
Eclipse returns error message “Java was started but returned exit code = 1”
... message points to a problem with your Java version. Do you have a JDK installed?
Try adding the following (noting the new line):
/!\ make sure, that the -vm option occurs before the -vmargs command.
Everything after -vmargs is passed directly to the JVM.
-vm
c:/wherever/java/jdk1.6.0_21/...
How to run code when a class is subclassed? [duplicate]
...- Watcher subclasses type, not object. 2 - SuperClass has no superclass at all, not object. I'm just so used to writing down object as a superclass for every class I defined that I somehow missed it that this code was using something else. Although there doesn't seem to be any harm in making SuperCl...
How do you use version control with Access development?
...an Access solution. It has a good amount of VBA, a number of queries, a small amount of tables, and a few forms for data entry & report generation. It's an ideal candidate for Access.
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Create a “with” block on several context managers? [duplicate]
...rite:
with A() as X, B() as Y, C() as Z:
do_something()
This is normally the best method to use, but if you have an unknown-length list of context managers you'll need one of the below methods.
In Python 3.3, you can enter an unknown-length list of context managers by using contextlib.Exit...
How to apply bindValue method in LIMIT clause?
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@Ross I cannot specifically answer this- but I can point out that LIMIT and OFFSET are features that were glued on AFTER all this PHP/MYSQL/PDO madness hit the dev circuit... In fact, I believe it was Lerdorf himself who oversaw LIMIT implementatio...