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Is there shorthand for returning a default value if None in Python? [duplicate]
In C#, I can say x ?? "" , which will give me x if x is not null, and the empty string if x is null. I've found it useful for working with databases.
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Why would I want stage before committing in Git?
I'm new to version control and I understand that "committing" is essentially creating a backup while updating the new 'current' version of what you're working on.
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Intercept page exit event
... page within my system, a user might decide to navigate to another website and in doing so could lose all the edits they have not saved.
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How to evaluate a math expression given in string form?
...ntext with user input. The executed JavaScript can access all Java classes and thus hijack your application without limit.
– Boann
Sep 21 '15 at 11:08
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How to set child process' environment variable in Makefile
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I have GNU make 3.81, and all: <\n\t>export PROJ_ROOT=$(CURDIR)<\n\t>echo $(PROJ_ROOT)<\n> outputs the correct expansion for the first row, but only echo for the second one. PROJ_ROOT is not set after running make. Spaces around ...
What is the copy-and-swap idiom?
What is this idiom and when should it be used? Which problems does it solve? Does the idiom change when C++11 is used?
5 An...
Determine if a function exists in bash
...t tests which are executed from bash. Unit tests are initialized, executed and cleaned up in a bash script. This script usualy contains an init(), execute() and cleanup() functions. But they are not mandatory. I'd like to test if they are or are not defined.
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How to add some non-standard font to a website?
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Both Internet Explorer and Firefox re NOT based on Webkit, so it's quite a useless solution in my opinion.
– Casper
Sep 20 '08 at 13:21
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Java - Including variables within strings?
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I'm not sure if that is attractive enough for you, but it can be quite handy. The syntax is the same as for printf and java.util.Formatter. I've used it much especially if I want to show tabular numeric data.
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to remove first and last element in array
How to remove first and last element in an array?
12 Answers
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