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What is a word boundary in regex?
...put, among other purposes) and cannot find a precise definition of \b ("word boundary"). I had assumed that -12 would be an "integer word" (matched by \b\-?\d+\b ) but it appears that this does not work. I'd be grateful to know of ways of matching space-separated numbers.
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Confused about stdin, stdout and stderr?
...er confused with the purpose of these three files. If my understanding is correct, stdin is the file in which a program writes into its requests to run a task in the process, stdout is the file into which the kernel writes its output and the process requesting it accesses the information from, a...
How can I declare and use Boolean variables in a shell script?
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Revised Answer (Feb 12, 2014)
the_world_is_flat=true
# ...do something interesting...
if [ "$the_world_is_flat" = true ] ; then
echo 'Be careful not to fall off!'
fi
Original Answer
Caveats: https://stackoverflow.com/a/21210966/89391
the_world_is_fla...
Various ways to remove local Git changes
I just cloned a git repository and checked out a branch. I worked on it, and then decided to remove all my local changes, as I wanted the original copy.
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What is the difference between a URI, a URL and a URN?
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From RFC 3986:
A URI can be further classified as a locator, a name, or both. The
term "Uniform Resource Locator" (URL) refers to the subset of URIs
that, in addition to identifying a resource, provide a means of
locating the resource by describing its primary acces...
What is “assert” in JavaScript?
... using some library that provides one. The usual meaning is to throw an error if the expression passed into the function is false; this is part of the general concept of assertion checking. Usually assertions (as they're called) are used only in "testing" or "debug" builds and stripped out of produc...
How to check if activity is in foreground or in visible background?
I have a splash screen on a timer. My problem is that before I finish() my activity I need to check that the next activity has started because a system dialogue box pops-up and I only want to finish() ; once the user has selected an option from the dialogue box?
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Understanding checked vs unchecked exceptions in Java
...e say that checked exceptions (i.e. these that you should explicitly catch or rethrow) should not be used at all. They were eliminated in C# for example, and most languages don't have them. So you can always throw a subclass of RuntimeException (unchecked exception)
However, I think checked excepti...
Defining a variable with or without export
What is export for?
14 Answers
14
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Servlet returns “HTTP Status 404 The requested resource (/servlet) is not available”
I have an HTML form in a JSP file in my WebContent/jsps folder. I have a servlet class servlet.java in my default package in src folder. In my web.xml it is mapped as /servlet .
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