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How to detect which one of the defined font was used in a web page?
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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
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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...
How to retry after exception?
... while True:
try:
# do stuff
except SomeSpecificException:
continue
break
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What is the reason for performing a double fork when creating a daemon?
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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.
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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()...
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
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How can I convert a zero-terminated byte array to string?
... read. You should save that number and then use it to create your string. If n is the number of bytes read, your code would look like this:
s := string(byteArray[:n])
To convert the full string, this can be used:
s := string(byteArray[:len(byteArray)])
This is equivalent to:
s := string(byteArray...
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 ...