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Capturing Groups From a Grep RegEx
...egex="[0-9]+_([a-z]+)_[0-9a-z]*"
for f in $files # unquoted in order to allow the glob to expand
do
if [[ $f =~ $regex ]]
then
name="${BASH_REMATCH[1]}"
echo "${name}.jpg" # concatenate strings
name="${name}.jpg" # same thing stored in a variable
else
...
What does a type followed by _t (underscore-t) represent?
...
As Douglas Mayle noted, it basically denotes a type name. Consequently, you would be ill-advised to end variable or function names with '_t' since it could cause some confusion. As well as size_t, the C89 standard defines wchar_t, off_t, ptrdiff_t, and p...
Performance difference for control structures 'for' and 'foreach' in C#
...t will depend on whether you're doing any real work in the loop. In almost all cases, the difference to performance won't be significant, but the difference to readability favours the foreach loop.
I'd personally use LINQ to avoid the "if" too:
foreach (var item in list.Where(condition))
{
}
EDI...
Is this object-lifetime-extending-closure a C# compiler bug?
...L_000e: ldloc.0
IL_000f: ldc.r8 42
IL_0018: ldc.r8 1
IL_0021: call float64 [mscorlib]System.Math::Pow(float64, float64)
IL_0026: stfld float64 ConsoleApplication1.Program/Foo/'<>c__DisplayClass1'::capturedVariable
IL_002b: ldarg.0
IL_002c: ldloc.0
IL_002d: ldftn ins...
Why would you use an ivar?
I usually see this question asked the other way, such as Must every ivar be a property? (and I like bbum's answer to this Q).
...
How do I convert between big-endian and little-endian values in C++?
...
If you're using Visual C++ do the following: You include intrin.h and call the following functions:
For 16 bit numbers:
unsigned short _byteswap_ushort(unsigned short value);
For 32 bit numbers:
unsigned long _byteswap_ulong(unsigned long value);
For 64 bit numbers:
unsigned __int64 _byt...
Get event listeners attached to node using addEventListener
...
You can't.
The only way to get a list of all event listeners attached to a node is to intercept the listener attachment call.
DOM4 addEventListener
Says
Append an event listener to the associated list of event listeners with type set to type, listener set to ...
python multithreading wait till all threads finished
...oin method of Thread object in the end of the script.
t1 = Thread(target=call_script, args=(scriptA + argumentsA))
t2 = Thread(target=call_script, args=(scriptA + argumentsB))
t3 = Thread(target=call_script, args=(scriptA + argumentsC))
t1.start()
t2.start()
t3.start()
t1.join()
t2.join()
t3.join...
How can I handle time zones in my webapp?
...
The majority of your users probably will not change timezones much, or at all. For the most part, the situation you outlined is uncommon. By implementing a dropdown with a suitable default, you should be able to make things easy enough for those who do move around (because they typically have a bet...
In which case do you use the JPA @JoinTable annotation?
... project_id
name name task_id
The Project_Tasks table is called a "Join Table". To implement this second solution in JPA you need to use the @JoinTable annotation. For example, in order to implement a uni-directional one-to-many association, we can define our entities as such:
Proj...