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Determine if variable is defined in Python [duplicate]
... something like defined() in Perl or isset() in PHP or defined? in Ruby.
6 Answers
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Importing data from a JSON file into R
... answered Aug 1 '17 at 8:40
Moby MMoby M
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How to select lines between two marker patterns which may occur multiple times with awk/sed
...bc$/,/^mno$/{ /^abc$/d; /^mno$/d; p; }'
The -n option means do not print by default.
The pattern looks for lines containing just abc to just mno, and then executes the actions in the { ... }. The first action deletes the abc line; the second the mno line; and the p prints the remaining lines. Y...
How to write a foreach in SQL Server?
...ng cursors left and right. They are needed <1% of the time. RBAR (row by agonizing row) solutions are typically bad performers and cause headaches. If you are new, PLEASE try to learn this lesson early.
– granadaCoder
Aug 29 '13 at 14:56
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How do I add an existing directory tree to a project in Visual Studio?
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Its working! I was trying to create a shortcut by right-clicking the folder, instead of using the command prompt and thus it did not work. Following the steps described above fixed the issue. Thanks
– Anoop K. Prabhu
Dec 3 '14 at 9:2...
Undoing a 'git push'
...t; git status
# On branch master
# Your branch is ahead of 'origin/master' by 1 commit.
#
nothing to commit (working directory clean)
prompt>
Replace 35f6af6f77f116ef922e3d75bc80a4a466f92650 with your own commit.
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Case-Insensitive List Search
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As of .NET 2.0, this is now easily done - look at shaxby's answer below.
– Joe
May 28 '13 at 20:57
3
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Is there a null-coalescing (Elvis) operator or safe navigation operator in javascript?
I'll explain by example:
21 Answers
21
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How to duplicate object properties in another object?
...t,
...secondObject
}
This avoids problems of passing these objects by reference.
Additionally it takes care of objects that have deep nesting.
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Permanently add a directory to PYTHONPATH?
...o add your new directory to the environment variable PYTHONPATH, separated by a colon from previous contents thereof. In any form of Unix, you can do that in a startup script appropriate to whatever shell you're using (.profile or whatever, depending on your favorite shell) with a command which, ag...