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Difference between static STATIC_URL and STATIC_ROOT on Django
...file.
This causes a silent failure in django/conf/urls/static.py.
The test elif not settings.DEBUG or '://' in prefix:
picks up the '//' in the URL and does not add the static URL pattern, causing no static files to be found.
It would be thoughtful if Django spit out an error message stating...
Select random row from a sqlite table
...0, count). MAX is used to handle a case with empty table.
Here are simple test results on a table with 16k rows:
sqlite> .timer on
sqlite> select count(*) from payment;
16049
Run Time: real 0.000 user 0.000140 sys 0.000117
sqlite> select payment_id from payment limit 1 offset abs(random(...
Difference between open and codecs.open in Python
...
In Python 2 there are unicode strings and bytestrings. If you just use bytestrings, you can read/write to a file opened with open() just fine. After all, the strings are just bytes.
The problem comes when, say, you have a unicode string and you do the following:
>...
Composer: how can I install another dependency without updating old ones?
...led with the message:
Warning: The lock file is not up to date with the latest changes in composer.json.
You may be getting outdated dependencies. Run update to update them.
Your requirements could not be resolved to an installable set of packages.
I tried to run the solution from Seldaek issuing...
Safe (bounds-checked) array lookup in Swift, through optional bindings?
...oth levels)
does not lead to problems for Sets
concise code
Here are some tests I ran for you:
let itms: [Int?] = [0, nil]
let a = itms[safe: 0] // 0 : Int??
a ?? 5 // 0 : Int?
let b = itms[safe: 1] // nil : Int??
b ?? 5 // nil : Int? (`b` contains a value and that value is `nil`)
let c = itms[safe...
What does the [Flags] Enum Attribute mean in C#?
... You cannot use the None enumerated constant in a bitwise AND operation to test for a flag because the result is always zero. However, you can perform a logical, not a bitwise, comparison between the numeric value and the None enumerated constant to determine whether any bits in the numeric value ar...
When a 'blur' event occurs, how can I find out which element focus went *to*?
...gName||target : '';
}, 1);
}
This should work in most modern browsers (tested in Chrome, IE, and Firefox), with the caveat that Chrome does not set focus on buttons that are clicked (vs. tabbed to).
share
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...
Why can't I use a list as a dict key in python?
...std. dev. of 7 runs, 10000000 loops each)
As you can see, the membership test in our stupidlists_set is even slower than a linear scan over the whole lists_list, while you have the expected super fast lookup time (factor 500) in a set without loads of hash collisions.
TL; DR: you can use tuple(...
Can a decorator of an instance method access the class?
...r you could use a class decorator, perhaps something like this (warning: untested code).
def class_decorator(cls):
for name, method in cls.__dict__.iteritems():
if hasattr(method, "use_class"):
# do something with the method and class
print name, cls
return cls...
What is a bus error?
...SIGBUS. */
*map = 0;
}
Run with:
gcc -std=c99 main.c -lrt
./a.out
Tested in Ubuntu 14.04.
POSIX describes SIGBUS as:
Access to an undefined portion of a memory object.
The mmap spec says that:
References within the address range starting at pa and continuing for len bytes to whol...