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How to override the [] operator in Python?
...rwise this will happen:
>>> myobj[5] = 1
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: MyClass instance has no attribute '__setitem__'
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Python integer incrementing with ++ [duplicate]
...I've looked back at my VB6 days and thought, "What modern language doesn't allow incrementing with double plus signs?":
7 A...
Location of my.cnf file on macOS
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This thread on the MySQL forum says:
By default, the OS X installation does not use a my.cnf, and MySQL just uses the default values. To set up your own my.cnf, you could just create a file straight in /etc.
OS X provides example configuration files at /usr/local/mysql/support-files/...
In Django, how do I check if a user is in a certain group?
...add(group) # user is now in the "Editor" group
then user.groups.all() returns [<Group: Editor>].
Alternatively, and more directly, you can check if a a user is in a group by:
if django_user.groups.filter(name = groupname).exists():
...
Note that groupname can also be the ac...
Match multiple cases classes in scala
... matcher(l: Foo): String = {
l match {
case A() => "A"
case B(_) | C(_) => "B"
case _ => "default"
}
}
If you must, must, must extract the parameter and treat them in the same code block, you could:
def matcher(l: Foo): String = {
l match {
case A() => "A"
ca...
How to avoid 'cannot read property of undefined' errors?
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Catching all exceptions without re-throwing is bad, and generally using exceptions as part of the expected flow of execution is also not great -- even though in this case it's pretty well contained.
– hugo
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PHP: How to send HTTP response code?
...-Code: 404', true, 404);
I recommend the 2nd one. The first does work on all browsers I have tested, but some minor browsers or web crawlers may have a problem with a header line that only contains a colon. The header field name in the 2nd. variant is of course not standardized in any way and coul...
Check if a variable is a string in JavaScript
...ing both typeof and instanceof feels like good advice if your code may be called by others'. @MarkAmery's postmessage edge case matters if you're asking "what was I just postmessaged?" - but you'd expect that to be handled at the interface and not allowed to propagate. Elsewhere, it seems correct t...
Determine if code is running as part of a unit test
I have a unit test (nUnit). Many layers down the call stack a method will fail if it is running via a unit test.
19 Answers...
What do ellipsis […] mean in a list?
... an infinite loop of references, so it decided to cut it short, it's not really infinite. And no, it's not really useful besides a thought experiment :)
– Óscar López
Jun 18 '13 at 3:44
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