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How can I search Git branches for a file or directory?
...cript to use it, I found it a little restricted to use that approach.
Sometimes you need to search for something that can appear/disappear over time, so why not search against all commits? Besides that, sometimes you need a verbose response, and other times only commit matches. Here are two version...
Why does InetAddress.isReachable return false, when I can ping the IP address?
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// in case of Linux change the 'n' to 'c'
Process p1 = java.lang.Runtime.getRuntime().exec("ping -n 1 www.google.com");
int returnVal = p1.waitFor();
boolean reachable = (returnVal==0);
The -c option of ping will allow ping to simply try to reach the server once(as opposed to the in...
Why does i = i + i give me 0?
...
This is my favorite answer on this site ever of all times.
– Lee White
Jun 12 '14 at 14:24
2
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Haskell: Lists, Arrays, Vectors, Sequences
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The first problem with lists is that to index into them (!!) takes ϴ(k) time, which is annoying. Also, appends can be slow ++, but Haskell's lazy evaluation model means that these can be treated as fully amortized, if they happen at all.
The second problem with lists is that they have poor data ...
How do I efficiently iterate over each entry in a Java Map?
If I have an object implementing the Map interface in Java and I wish to iterate over every pair contained within it, what is the most efficient way of going through the map?
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DESTDIR and PREFIX of make
...Sepcify a different --prefix location/option for each build - at configure time. For eg:
untar petsc tar ball
./configure --prefix=/opt/petsc/petsc-3.9.0-mpich --with-mpi-dir=/opt/mpich
make
make install DESTDIR=/tmp/petsc-pkg
untar petsc tar ball
./configure --prefix=/opt/petsc/petsc-3.9.0-openmpi...
How to forward declare a C++ template class?
...e a templated class whose definition states the default arguments, but any time you reference the class you must include all of its arguments until the definition is introduced.
eg. Let's use std::vector without including it (the second argument of std::vector is defined with a default):
namespace s...
PHP abstract properties
..., there is no way to enforce that with the compiler, you'd have to use run-time checks (say, in the constructor) for the $tablename variable, e.g.:
class Foo_Abstract {
public final function __construct(/*whatever*/) {
if(!isset($this->tablename))
throw new LogicException(get_class($...
What does “SyntaxError: Missing parentheses in call to 'print'” mean in Python?
...o!")?
Since the "Missing parentheses in call to print" case is a compile time syntax error and hence has access to the raw source code, it's able to include the full text on the rest of the line in the suggested replacement. However, it doesn't currently try to work out the appropriate quotes to p...
Do sessions really violate RESTfulness?
...ate of this key must be maintained and it has some sort of expiration date/time after which it no longer grants access. However, as I mentioned at the top of my post, sacrifices must be made to allow an application to actually work. That said, authentication tokens must be stored in a way that all...