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Can I use __init__.py to define global variables?
... This should have been the accepted answer. If you are working with Python 2.5 or higher you can also use an explicit relative import as well as described here: from . import MY_CONSTANT
– ThatAintWorking
Feb 12 '14 at 17:17
...
Swift 编程语言入门教程 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...的值是可选值。
let optionalSquare: Square? = Square(sideLength: 2.5, name: "optional square")
let sideLength = optionalSquare?.sideLength
7 枚举与结构
使用 enum 来创建枚举。有如类和其他命名类型，枚举可以有方法。
enum Rank: Int {
case Ace...
What's the difference between HEAD, working tree and index, in Git?
...
Note that Git 2.5 will bring multiple working trees (stackoverflow.com/a/30185564/6309). +1
– VonC
Jun 2 '15 at 17:34
3...
Adding an identity to an existing column
....
I've used this trick to convert, in under 5 seconds, a column of a of a 2.5 billion row table from IDENTITY to a non-IDENTITY (in order to run a multi-hour query whose query plan worked better for non-IDENTITY columns), and then restored the IDENTITY setting, again in less than 5 seconds.
Here's...
Is it worth using Python's re.compile?
...ference to be negligible.
EDIT:
After a quick glance at the actual Python 2.5 library code, I see that Python internally compiles AND CACHES regexes whenever you use them anyway (including calls to re.match()), so you're really only changing WHEN the regex gets compiled, and shouldn't be saving muc...
How can I change my Cygwin home folder after installation?
...etween the various methods. When I use db_home: windows, it takes sh about 2.5 to 3.5 seconds to start. When I use db_home: /cygdrive/c/Users/%U, it takes sh about 0.9 to 1.0 seconds to start. When I delete the db_home line or hard-code it to the Windows home directory, sh takes about 0.2 to 0.3 sec...
Does “git fetch --tags” include “git fetch”?
...om the remote in addition to whatever else is being fetched.
Since Git 2.5 (Q2 2015) git pull --tags is more robust:
See commit 19d122b by Paul Tan (pyokagan), 13 May 2015.
(Merged by Junio C Hamano -- gitster -- in commit cc77b99, 22 May 2015)
pull: remove --tags error in no merge candidat...
Python: fastest way to create a list of n lists
...Python loop using
d = numpy.empty((n, 0)).tolist()
but this is actually 2.5 times slower than the list comprehension.
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Why not infer template parameter from constructor?
...constructor arguments.
Examples:
std::pair p(2, 4.5);
std::tuple t(4, 3, 2.5);
Accepted paper.
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What is the best way to implement nested dictionaries?
...w instance.
This approach has been available (and documented) since Python 2.5, and (particularly valuable to me) it pretty prints just like a normal dict, instead of the ugly printing of an autovivified defaultdict:
class Vividict(dict):
def __missing__(self, key):
value = self[key] = t...