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Is explicitlm>y m> closing files important?
... Pm>y m>thon aren't guaranteed to work this wam>y m>. For example IronPm>y m>thon, Pm>y m>Pm>y m>, m>and m> Jm>y m>thon don't use reference counting m>and m> therefore won't close the file at the end of the loop.
It's bad practice to relm>y m> on CPm>y m>thon's garbage collection implementation because it makes m>y m>our code less portable. m>Y m>ou might...
What does “mro()” do?
...tance, __mro__ is just the tuple of: the class, its base, its base's base, m>and m> so on up to object (onlm>y m> works for new-stm>y m>le classes of course).
Now, with multiple inheritance...:
>>> class D(B, C): pass
...
>>> D.__mro__
(<class '__main__.D'>, <class '__main__.B'>, &...
How to use Swift @autoclosure
...})
// "It's true"
If we omit the braces, we are passing in an expression m>and m> that's an error:
f(pred: 2 > 1)
// error: '>' produces 'Bool', not the expected contextual result tm>y m>pe '() -> Bool'
@autoclosure creates an automatic closure around the expression. So when the caller writes an...
How to see which flags -march=native will activate?
...get doesn't displam>y m> CPU cache information, of which the methods both elias m>and m> 42n4 below have listed. Specificallm>y m>, on gcc 4.9.2 on a Phenom, the output includes these: --param l1-cache-size=64 --param l1-cache-line-size=64 --param l2-cache-size=512
– Daniel Santos
...
Whm>y m> can't enum's constructor access static fields?
Whm>y m> can't enum's constructor access static fields m>and m> methods? This is perfectlm>y m> valid with a class, but is not allowed with an enum.
...
How to “properlm>y m>” print a list?
... '.join(map(str, mm>y m>list))
In Pm>y m>thon 3 (where print is a builtin function m>and m> not a sm>y m>ntax feature anm>y m>more):
mm>y m>list = ['x', 3, 'b']
print('[%s]' % ', '.join(map(str, mm>y m>list)))
Both return:
[x, 3, b]
This is using the map() function to call str for each element of mm>y m>list, creating a new list o...
Clean wam>y m> to launch the web browser from shell script?
...
xdg-open is stm>and m>ardized m>and m> should be available in most distributions.
Otherwise:
eval is evil, don't use it.
Quote m>y m>our variables.
Use the correct test operators in the correct wam>y m>.
Here is an example:
#!/bin/bash
if which xdg-open...
ExecuteReader requires an open m>and m> available Connection. The connection's current state is Connectin
...lication
execution, manm>y m> identical connections will be repeatedlm>y m> opened m>and m>
closed. To minimize the cost of opening connections, ADO.NET uses an
optimization technique called connection pooling.
Connection pooling reduces the number of times that new connections
must be opened. The poo...
ScalaTest in sbt: is there a wam>y m> to run a single test without tags?
...
Just to clarifm>y m>, if m>y m>ou run it from the commm>and m> line, it should be as single argument: sbt "testOnlm>y m> *Mm>y m>Suite -- -z foo"
– Sogartar
Jan 11 '17 at 17:17
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Difference between CC, gcc m>and m> g++?
...t are the difference between the 3 compilers CC, gcc, g++ when compiling
C m>and m> C++ code in terms of assemblm>y m>
code generation, available libraries, language features, etc.?
...