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Create empty file using python [duplicate]
...mknod("newfile.txt") (but it requires root privileges on OSX). The system call to create a file is actually open() with the O_CREAT flag. So no matter how, you'll always open the file.
So the easiest way to simply create a file without truncating it in case it exists is this:
open(x, 'a').close()
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Virtual functions and performance - C++
...e a very slight effect on performance, but it's unlikely to affect the overall performance of your application. Better places to look for performance improvements are in algorithms and I/O.
An excellent article that talks about virtual functions (and more) is Member Function Pointers and the Fastes...
Calling Python in Java?
...yObject someFunc = interpreter.get("funcName");
PyObject result = someFunc.__call__(new PyString("Test!"));
String realResult = (String) result.__tojava__(String.class);
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How can I remove a character from a string using Javascript?
I am so close to getting this, but it just isn't right.
All I would like to do is remove the character r from a string.
The problem is, there is more than one instance of r in the string.
However, it is always the character at index 4 (so the 5th character).
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\r\n, \r and \n what is the difference between them? [duplicate]
... \r is for Mac OS 9 and under (also back in the days when it was called System). Mac OS X mostly uses \n (and is a Unix).
– Bruno
Mar 15 '13 at 13:51
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HashSet versus Dictionary w.r.t searching time to find if an item exists
...s for Dictionary is so fast that there is no benefit from using HashSet at all, in the OP's case.
– EtherDragon
Jul 27 '12 at 23:03
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Python unittests in Jenkins?
...ittest.TestCase):
@unittest.skip("demonstrating skipping")
def test_skipped(self):
self.fail("shouldn't happen")
def test_pass(self):
self.assertEqual(10, 7 + 3)
def test_fail(self):
self.assertEqual(11, 7 + 3)
JUnit with pytest
run the tests with:
py.te...
Cannot push to Heroku because key fingerprint
... I followed this post and others of the same kind without success :-((
Finally, I found the solution:
I had to add my new rsa identity in my machine!
So, first of all I created a new rsa key:
ssh-keygen -t rsa -C "giordano.scalzo[at]gmail.com" -f ~/.ssh/id_rsa_heroku
then added it to my machin...
Why do some claim that Java's implementation of generics is bad?
I've occasionally heard that with generics, Java didn't get it right. (nearest reference, here )
13 Answers
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Why is Scala's immutable Set not covariant in its type?
...ameter of type A due to the contravariance of functions. Set could potentially be contravariant in A, but this too causes issues when you want to do things like this:
def elements: Iterable[A]
In short, the best solution is to keep things invariant, even for the immutable data structure. You'll...