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Python (and Python C API): __new__ versus __init__
...vs immutable types.
__new__ accepts a type as the first argument, and (usually) returns a new instance of that type. Thus it is suitable for use with both mutable and immutable types.
__init__ accepts an instance as the first argument and modifies the attributes of that instance. This is inappropr...
What does __FILE__ mean in Ruby?
I see this all the time in Ruby:
4 Answers
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cancelling a handler.postdelayed process
...nnable, SPLASH_DISPLAY_LENGTH);
And this to remove it: myHandler.removeCallbacks(myRunnable);
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Bulk insert with SQLAlchemy ORM
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You also need s.commit() to actually save the records (it took me a bit to figure this one out).
– horcle_buzz
Dec 4 '15 at 1:30
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Downloading Java JDK on Linux via wget is shown license page instead
...2b6607d096fa80163/jdk-8u131-linux-x64.rpm > jdk-8u112-linux-x64.rpm
In all cases above, subst 'i586' for 'x64' to download the 32-bit build.
-j -> junk cookies
-k -> ignore certificates
-L -> follow redirects
-H [arg] -> headers
curl can be used in place of wget.
UPDATE FOR JDK 7u7...
When should iteritems() be used instead of items()?
Is it legitimate to use items() instead of iteritems() in all places? Why was iteritems() removed from Python 3? Seems like a terrific and useful method. What's the reasoning behind it?
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What does the caret operator (^) in Python do?
...his way:
1000 # 8 (binary)
0011 # 3 (binary)
---- # APPLY XOR ('vertically')
1011 # result = 11 (binary)
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What happens to global and static variables in a shared library when it is dynamically linked?
...and what happens when modules with globals and static variables are dynamically linked to an application.
By modules, I mean each project in a solution (I work a lot with visual studio!). These modules are either built into *.lib or *.dll or the *.exe itself.
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Why is parenthesis in print voluntary in Python 2.7?
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In Python 2.x print is actually a special statement and not a function*.
This is also why it can't be used like: lambda x: print x
Note that (expr) does not create a Tuple (it results in expr), but , does. This likely results in the confusion between...
Why is the order in dictionaries and sets arbitrary?
...der:
>>> {'bar': None, 'foo': None}
{'foo': None, 'bar': None}
All slots except 3 and 4 are empty, looping over the table first lists slot 3, then slot 4, so 'foo' is listed before 'bar'.
bar and baz, however, have hash values that are exactly 8 apart and thus map to the exact same slot...