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What is PECS (Producer Extends Consumer Super)?
I came across PECS (short for Producer extends and Consumer super ) while reading up on generics.
14 Answers
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Catch multiple exceptions at once?
...
Catch System.Exception and switch on the types
catch (Exception ex)
{
if (ex is FormatException || ex is OverflowException)
{
WebId = Guid.Empty;
return;
}
throw;
}
...
How can I count the number of matches for a regex?
...r Java 9+
long matches = matcher.results().count();
Solution for Java 8 and older
You'll have to do the following. (Starting from Java 9, there is a nicer solution)
int count = 0;
while (matcher.find())
count++;
Btw, matcher.groupCount() is something completely different.
Complete exampl...
Parse (split) a string in C++ using string delimiter (standard C++)
...npos) function returns a substring of the object, starting at position pos and of length npos.
If you have multiple delimiters, after you have extracted one token, you can remove it (delimiter included) to proceed with subsequent extractions (if you want to preserve the original string, just use...
How do you implement a “Did you mean”? [duplicate]
...
Actually what Google does is very much non-trivial and also at first counter-intuitive. They don't do anything like check against a dictionary, but rather they make use of statistics to identify "similar" queries that returned more results than your query, the exact algorithm...
The best way to remove duplicate values from NSMutableArray in Objective-C?
...wrote the answer below in 2009; in 2011, Apple added NSOrderedSet to iOS 5 and Mac OS X 10.7. What had been an algorithm is now two lines of code:
NSOrderedSet *orderedSet = [NSOrderedSet orderedSetWithArray:yourArray];
NSArray *arrayWithoutDuplicates = [orderedSet array];
If you are worried ab...
How to position text over an image in css
...ke this: http://jsfiddle.net/EgLKV/3/
Its done by using position:absolute and z-index to place the text over the image.
#container {
height: 400px;
width: 400px;
position: relative;
}
#image {
position: absolute;
left: 0;
top: 0;
}
#text {
z-index: 100;
position: ab...
Threading pool similar to the multiprocessing Pool?
...ool interface in the multiprocessing module, however it is hidden somewhat and not properly documented.
It can be imported via
from multiprocessing.pool import ThreadPool
It is implemented using a dummy Process class wrapping a python thread. This thread-based Process class can be found in mult...
Numbering rows within groups in a data frame
...g this approach, make sure that you are not getting conflicts between plyr and dplyr as explained in this post It can be avoided by explicitly calling dplyr::mutate(...)
– EcologyTom
Apr 10 '18 at 14:16
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Can't import my own modules in Python
I'm having a hard time understanding how module importing works in Python (I've never done it in any other language before either).
...