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variable === undefined vs. typeof variable === “undefined”
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For undeclared variables, typeof foo will return the string literal "undefined", whereas the identity check foo === undefined would trigger the error "foo is not defined".
For local variables (which you know are declared somewhere), no such error would occur, hence the identity check....
Build project into a JAR automatically in Eclipse
...matically builds a project's .class files and put them in target folder; it should also build a JAR automatically and copy the latest JAR at some or a specific location.
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How to define Gradle's home in IDEA?
...Gradle project into IntelliJ, and when I get to the Gradle Home textbox, it is not automatically populated, nor will typing in the path of Gradle Home result in a valid location - I have the GRADLE_USER_HOME environment variable set (to what I think is!) the correct path, and I have been able ...
How to delete all files and folders in a directory?
...etFiles(), because when you use EnumerateFiles() you can start enumerating it before the whole collection is returned, as opposed to GetFiles() where you need to load the entire collection in memory before begin to enumerate it. See this quote here:
Therefore, when you are working with many file...
How can I indent multiple lines in Xcode?
When I select multiple lines of code and want to indent them as usual with TAB key, it just deletes them all. I come from Eclipse where I always did it that way. How's that done in Xcode? I hope not line by line ;)
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MySQL indexes - what are the best practices?
...that I will be searching or selecting using a WHERE clause but sometimes it doesn't seem so black and white.
7 Answers
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How to round a number to significant figures in Python
...gt;> round(1234, -3)
1000.0
Thus if you need only most significant digit:
>>> from math import log10, floor
>>> def round_to_1(x):
... return round(x, -int(floor(log10(abs(x)))))
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>>> round_to_1(0.0232)
0.02
>>> round_to_1(1234243)
1000000.0
>>&g...
How to upgrade Git to latest version on macOS?
I just bought a new Mac with OS X Lion and I checked in the Terminal what version of git is installed by default. I got the answer
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foreach vs someList.ForEach(){}
There are apparently many ways to iterate over a collection. Curious if there are any differences, or why you'd use one way over the other.
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Fastest method of screen capturing on Windows
I want to write a screencasting program for the Windows platform, but am unsure of how to capture the screen. The only method I'm aware of is to use GDI, but I'm curious whether there are other ways to go about this, and, if there are, which incurs the least overhead? Speed is a priority.
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