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What Makes a Method Thread-safe? What are the rules?
...nderstand that there are probably a million one-off situations, but what about in general? Is it this simple?
4 Answers
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What's the difference between event.stopPropagation and event.preventDefault?
...ul to know what the default action is for a button click so I can reason about why stopDefault() doesn't work the same way as stopPropagation(). If the default action isn't calling the onclick method what is it?
– d512
Jun 21 '19 at 22:33
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Servlet returns “HTTP Status 404 The requested resource (/servlet) is not available”
...te that the /jsps subfolder is not strictly necessary. You can even do without it and put the JSP file directly in webcontent/webapp root, but I'm just taking over this from your question.
Set servlet URL in url-pattern
The servlet URL is specified as the "URL pattern" of the servlet mapping. It's...
Scala type programming resources
...or guaranteeing that certain types fields exist in all implementations without forcing an implementation. In the lambda calculus example, this corresponds to trait Lambda that guarantees that the following types exist: subst, apply, and eval.
Next: define subtraits that extend the abstract trait and...
Reference: Comparing PHP's print and echo
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Why two constructs?
The truth about print and echo is that while they appear to users as two distinct constructs, they are both really shades of echo if you get down to basics, i.e. look at the internal source code. That source code involves the parser as w...
Are arrays in PHP copied as value or as reference to new variables, and when passed to functions?
...
}
$arr = array(10, 20);
my_func($arr);
var_dump($arr);
It'll give this output :
array
0 => int 10
1 => int 20
Which indicates the function has not modified the "outside" array that was passed as a parameter : it's passed as a copy, and not a reference.
If you want it passed by refe...
Multiprocessing - Pipe vs Queue
...ccounts for tasks when queue.task_done() is called (it doesn't even know about the specific task, it just counts unfinished tasks in the queue), so that queue.join() knows the work is finished.
The code for each at bottom of this answer...
mpenning@mpenning-T61:~$ python multi_pipe.py
Sending 100...
How do you do a deep copy of an object in .NET? [duplicate]
...r constructors are doing heavy lifting such as event subscription, you are out of luck. It relies on copying private fields of the object, bypassing the business logic in the properties and methods. For example, I saw hashCode field being copied in a HashSet collection, even though all instances hav...
std::vector versus std::array in C++
...ee different unrelated meanings, and the term is also used often to talk about stuff that is fixed at compile time. I hope that "statically-sized" is a bit more clear.
– Matteo Italia
Oct 21 '14 at 12:55
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How do I find the duplicates in a list and create another list with them?
..., hence the need for not).
To compute the list of duplicated elements without libraries:
seen = {}
dupes = []
for x in a:
if x not in seen:
seen[x] = 1
else:
if seen[x] == 1:
dupes.append(x)
seen[x] += 1
If list elements are not hashable, you cannot u...