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if A vs if A is not None:
...
The statement
if A:
will call A.__nonzero__() (see Special method names documentation) and use the return value of that function. Here's the summary:
object.__nonzero__(self)
Called to implement truth value testing and the built-in operation ...
Pandas selecting by label sometimes return Series, sometimes returns DataFrame
...answered Dec 4 '13 at 19:36
Dan AllanDan Allan
27.4k66 gold badges6060 silver badges6060 bronze badges
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how to break the _.each function in underscore.js
...t provide to escape the loop (other than throwing an exception).
However, all hope is not lost! You can use the Array.every method. :)
From that link:
every executes the provided callback function once for each element present in the array until it finds one where callback returns a false valu...
Looping through a hash, or using an array in PowerShell
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VertigoRayVertigoRay
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How to replace multiple strings in a file using PowerShell
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KyleMit
54.2k4747 gold badges332332 silver badges499499 bronze badges
answered Aug 4 '10 at 7:10
dahlbykdahlbyk
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How do I view the type of a scala expression in IntelliJ
... think this is what I'm looking for, Ctrl + Q only works for variables not all expressions.
– Jon Freedman
Oct 22 '11 at 10:29
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Does ARC support dispatch queues?
...d as
* Objective-C types when building with an Objective-C compiler. This allows
* them to participate in ARC, in RR management by the Blocks runtime and in
* leaks checking by the static analyzer, and enables them to be added to Cocoa
* collections.
*
* NOTE: this requires explicit cancellati...
How do I use Ruby for shell scripting?
...r, options)
rm(list, options)
rm_r(list, options)
rm_rf(list, options)
install(src, dest, mode = <src's>, options)
chmod(mode, list, options)
chmod_R(mode, list, options)
chown(user, group, list, options)
chown_R(user, group, list, options)
touch(list, options)
Which is pretty nice
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Is 'float a = 3.0;' a correct statement?
...terals notation in specific scenarios.
For performance reasons:
Specifically, consider:
float foo(float x) { return x * 0.42; }
Here the compiler will emit a conversion (that you will pay at runtime) for each returned value. To avoid it you should declare:
float foo(float x) { return x * 0.42...
What are all the user accounts for IIS/ASP.NET and how do they differ?
Under Windows Server 2008 with ASP.NET 4.0 installed there is a whole slew of related user accounts, and I can't understand which one is which, how to they differ, and which one is REALLY the one that my app runs under. Here's a list:
...