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Access nested dictionary items via a list of keys?
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@user1353510: different usecases call for different behaviour. The code here doesn't create intermediaries, no.
– Martijn Pieters♦
Feb 11 '15 at 12:04
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Python integer division yields float
...142857142857
100//35 => 2
100.//35 => 2.0 # floating-point result if divsor or dividend real
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Do try/catch blocks hurt performance when exceptions are not thrown?
... IL_001f: nop
IL_0020: nop
IL_0021: leave.s IL_002f //JUMP IF NO EXCEPTION
} // end .try
catch [mscorlib]System.Exception
{
IL_0023: stloc.0
IL_0024: nop
IL_0025: ldloc.0
IL_0026: call void [mscorlib]System.Console::WriteLine(object)
IL_002b: no...
What's the best way to trim std::string?
...pp>
std::string str("hello world! ");
boost::trim_right(str);
str is now "hello world!". There's also trim_left and trim, which trims both sides.
If you add _copy suffix to any of above function names e.g. trim_copy, the function will return a trimmed copy of the string instead of modifying...
Any gotchas using unicode_literals in Python 2.6?
...g (assuming it's ascii) and convert it to unicode and fails. It would work if you did print name + two.name.decode('utf-8').
The same thing can happen if you encode a string and try to mix them later.
For example, this works:
# encoding: utf-8
html = '<html><body>helló wörld</body...
Multiple columns index when using the declarative ORM extension of sqlalchemy
...my.Column class, we should use the class sqlalchemy.schema.Index to specify an index that contains multiple columns.
2 A...
CMake: Print out all accessible variables in a script
I'm wondering if there is a way to print out all accessible variables in CMake. I'm not interested in the CMake variables - as in the --help-variables option. I'm talking about my variables that I defined, or the variables defined by included scripts.
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How do I 'overwrite', rather than 'merge', a branch on another branch in Git?
...eckout B
$ echo 'B' > file2
$ git commit -m 'change on branch B' file2
Now, let's try the strategy option (doesn't really matter if we use theirs or ours for this explanation):
$ git merge -X ours A
$ cat file*
A
B
original
We end up with a merge of both branches' contents (branch "strategy-opt...
When to use volatile with multi threading?
...e semantics on volatile variables.
[Update for C++11]
The C++11 Standard now does acknowledge multithreading directly in the memory model and the lanuage, and it provides library facilities to deal with it in a platform-independant way. However the semantics of volatile still have not changed. v...
Undefined symbols for architecture i386: _OBJC_CLASS_$_SKPSMTPMessage", referenced from: error
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You can get this type of error if your class' .m file is not listed under the "Compile Sources" step of the "Build Phases" tab of your target. Normally Xcode does this for you, but sometimes it loses the plot and you need to add the .m file manually.
To d...