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Java logical operator short-circuiting
...operators "short-circuit", meaning they don't evaluate the right-hand side if it isn't necessary.
The & and | operators, when used as logical operators, always evaluate both sides.
There is only one case of short-circuiting for each operator, and they are:
false && ... - it is not ne...
What is the reason for performing a double fork when creating a daemon?
...
Looking at the code referenced in the question, the justification is:
Fork a second child and exit immediately to prevent zombies. This
causes the second child process to be orphaned, making the init
process responsible for its cleanup. And, since the first child...
How to trigger event when a variable's value is changed?
...of 1 then a certain piece of code is carried out.
I know that I can use an if statement but the problem is that the value will be changed in an asynchronous process so technically the if statement could be ignored before the value has changed.
...
Android - Setting a Timeout for an AsyncTask?
... Seems like it defeats the purpose of using AsyncTask to begin with if this timeout method runs on the main UI thread... Why not just use the handler approach that I describe in my question? Seems much more straightforward because the UI thread doesn't freeze up while waiting to run the Handl...
How to detect which one of the defined font was used in a web page?
...
I've seen it done in a kind of iffy, but pretty reliable way. Basically, an element is set to use a specific font and a string is set to that element. If the font set for the element does not exist, it takes the font of the parent element. So, what they ...
On Duplicate Key Update same as insert
I've searched around but didn't find if it's possible.
8 Answers
8
...
multiprocessing: How do I share a dict among multiple processes?
...essing import Process, Manager
def f(d):
d[1] += '1'
d['2'] += 2
if __name__ == '__main__':
manager = Manager()
d = manager.dict()
d[1] = '1'
d['2'] = 2
p1 = Process(target=f, args=(d,))
p2 = Process(target=f, args=(d,))
p1.start()
p2.start()
p1.join()...
Truncating floats in Python
...float f to n decimal places without rounding'''
s = '{}'.format(f)
if 'e' in s or 'E' in s:
return '{0:.{1}f}'.format(f, n)
i, p, d = s.partition('.')
return '.'.join([i, (d+'0'*n)[:n]])
This is valid in Python 2.7 and 3.1+. For older versions, it's not possible to get the ...
Find a pair of elements from an array whose sum equals a given number
... its index.
hash(arr[i]) = i
end-for
for i=0 to arr.length - 1 do
# if K-th element exists and it's different then we found a pair
if hash(K - arr[i]) != i
print "pair i , hash(K - arr[i]) has sum K"
end-if
end-for
...
What's the difference between [ and [[ in Bash? [duplicate]
...to the [ command. It has several enhancements that make it a better choice if you write scripts that target bash. My favorites are:
It is a syntactical feature of the shell, so it has some special behavior that [ doesn't have. You no longer have to quote variables like mad because [[ handles empty...