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Is there a Python equivalent of the C# null-coalescing operator?
In C# there's a null-coalescing operator (written as ?? ) that allows for easy (short) null checking during assignment:
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How do I use IValidatableObject?
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First off, thanks to @paper1337 for pointing me to the right resources...I'm not registered so I can't vote him up, please do so if anybody else reads this.
Here's how to accomplish what I was trying to do.
Validatable class:
public class ValidateMe : IV...
Iterating over each line of ls -l output
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Set IFS to newline, like this:
IFS='
'
for x in `ls -l $1`; do echo $x; done
Put a sub-shell around it if you don't want to set IFS permanently:
(IFS='
'
for x in `ls -l $1`; do echo $x; done)
Or use while | read instead:
ls -l $1 | while read x; do echo $x;...
Python: What OS am I running on?
...gt;>> import os
>>> os.name
'posix'
>>> import platform
>>> platform.system()
'Linux'
>>> platform.release()
'2.6.22-15-generic'
The output of platform.system() is as follows:
Linux: Linux
Mac: Darwin
Windows: Windows
See: platform — Access to underl...
What is the difference between require_relative and require in Ruby?
...at is relative to the file containing the require_relative statement.
For example, if you have unit test classes in the "test" directory, and data for them under the test "test/data" directory, then you might use a line like this in a test case:
require_relative "data/customer_data_1"
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sys.argv[1] meaning in script
...in simplified terms what the sys.argv[1] represents. Is it simply asking for an input?
9 Answers
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Adding a cross-reference to a subheading or anchor in another page
...le_) because it works across files, when section headings are changed, and for all builders that support cross-references.
RST, in General
The tools that convert RST files to HTML do not necessarily have a notion of collection. This is the case for instance if you rely on github to convert RST fi...
Accept function as parameter in PHP
... first, and didn't know what it was called exactly. Ah well, now I'll know for when I need to do this as well. Thanks.
– Rob
Apr 23 '10 at 17:01
3
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Assignment inside lambda expression in Python
...e 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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Rounding up to next power of 2
... want to write a function that returns the nearest next power of 2 number. For example if my input is 789, the output should be 1024. Is there any way of achieving this without using any loops but just using some bitwise operators?
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