大约有 40,000 项符合查询结果（耗时：0.0411秒） [XML]
Creating a singleton in Python
... a base class. Here is a sample implementation:
class Singleton(type):
_instances = {}
def __call__(cls, *args, **kwargs):
if cls not in cls._instances:
cls._instances[cls] = super(Singleton, cls).__call__(*args, **kwargs)
return cls._instances[cls]
class...
What's the bad magic number error?
...
Perhaps you need 'rm __pycache__/*pyc' now, because the pyc files are now in that folder.
– Arpad Horvath
Jun 2 '16 at 17:30
1...
Can you give a Django app a verbose name for use throughout the admin?
... the 1.8 docs (and current docs),
New applications should avoid default_app_config. Instead they should require the dotted path to the appropriate AppConfig subclass to be configured explicitly in INSTALLED_APPS.
Example:
INSTALLED_APPS = [
# ...snip...
'yourapp.apps.YourAppConfig',
]...
Resize image in PHP
...k with images.
With GD, for example, it's as simple as...
function resize_image($file, $w, $h, $crop=FALSE) {
list($width, $height) = getimagesize($file);
$r = $width / $height;
if ($crop) {
if ($width > $height) {
$width = ceil($width-($width*abs($r-$w/$h)));
...
Disable migrations when running unit tests in Django 1.7
...1.6. I defined a new settings module just for unit
tests called "settings_test.py", which imports * from the main
settings module and adds this line:
MIGRATION_MODULES = {"myapp": "myapp.migrations_not_used_in_tests"}
Then I run tests like this:
DJANGO_SETTINGS_MODULE="myapp.setti...
iOS: How to store username/password within an app?
...ta and kSecAttrAccount in Objective-C code, so be sure to cast them using (__bridge id), e.g., [keychainItem setObject:obj forKey:(__bridge id)kSecValueData];
– Joe Hankin
Apr 6 '13 at 23:13
...
How do I parse an ISO 8601-formatted date?
... and are okay to tolerate occasional misreads.
– ivan_pozdeev
Apr 23 '15 at 23:34
2
Agreed. An ex...
How do you use the ellipsis slicing syntax in Python?
...'d use it like this:
>>> class TestEllipsis(object):
... def __getitem__(self, item):
... if item is Ellipsis:
... return "Returning all items"
... else:
... return "return %r items" % item
...
>>> x = TestEllipsis()
>>> print ...
也来说说ReactOS的调试 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...调试的.所以我就找了先下fDebug的的代码.在D:\ReactOS\ReactOS_src\boot\freeldr\fdebug这个目录下.
这里我啰嗦下.源代码的路径别放到目录中有空格的文件夹中,有时会导致不能编译.例如,以前我把源码放在了D:\Program Files\ReactOS_src\boot\freeldr\...
What are type lambdas in Scala and what are their benefits?
...ction of Either[A, B]. The monad typeclass looks like this:
trait Monad[M[_]] {
def point[A](a: A): M[A]
def bind[A, B](m: M[A])(f: A => M[B]): M[B]
}
Now, Either is a type constructor of two arguments, but to implement Monad, you need to give it a type constructor of one argument. The sol...