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Java: Calling a super method which calls an overridden method
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The keyword super doesn't "stick". Every method call is handled individually, so even if you got to SuperClass.method1() by calling super, that doesn't influence any other method call that you might make in the future.
That means there is no direct way to call SuperClass.m...
Why won't my PHP app send a 404 error?
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Your code is technically correct. If you looked at the headers of that blank page, you'd see a 404 header, and other computers/programs would be able to correctly identify the response as file not found.
Of course, your users are still SOL. N...
Manually raising (throwing) an exception in Python
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How do I manually throw/raise an exception in Python?
Use the most specific Exception constructor that semantically fits your issue.
Be specific in your message, e.g.:
raise ValueError('A very specific bad thing happened.')
Don't ...
“is” operator behaves unexpectedly with integers
...3):
The current implementation keeps an
array of integer objects for all
integers between -5 and 256, when you
create an int in that range you
actually just get back a reference to
the existing object. So it should be
possible to change the value of 1. I
suspect the behaviour of Py...
What is the meaning and difference between subject, user and principal?
...utomation, applications, connections, etc.
User - A subset of principal usually referring to a human operator. The distinction is blurring over time because the words "user" or "user ID" are commonly interchanged with "account". However, when you need to make the distinction between the broad clas...
How do I check if a number evaluates to infinity?
...ine but it won't be so obvious to maintainers of your code what you're actually trying to test for. I agree that using isFinite is almost always the better way to do things -- that's why I mentioned it in my answer -- but only the OP can decide whether it meets their requirements.
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Convert a row of a data frame to vector
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Might have been changed in the meantime, but today unlist allows dropping names: identical(unlist(df[1,], use.names = FALSE), as.numeric(df[1,])) (and btw df still is not a sensible name for a data.frame... ;-))
– Andri Signorell
Sep 25 '1...
Ruby replace string with captured regex pattern
...d answer first without reading the entirety of answers. That seems to generally be the most efficient means of fixing a problem. Give Vicky a break! :)
– Josh M.
Jan 31 '14 at 3:43
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Circular list iterator in Python
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Output:
a b c a b c ...
(Loops forever, obviously)
In order to manually advance the iterator and pull values from it one by one, simply call next(pool):
>>> next(pool)
'a'
>>> next(pool)
'b'
share...
Get value from SimpleXMLElement Object
... i can't believe this is so complicated. why would they make a class called "getName" but not "getValue"? why would they print empty string if you printed it instead of converted it manually to (string). WHY??
– user151496
Oct 17 '16 at 12:31
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