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Access multiple elements of list knowing their index
...
Alternatives:
>>> map(a.__getitem__, b)
[1, 5, 5]
>>> import operator
>>> operator.itemgetter(*b)(a)
(1, 5, 5)
share
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impro...
What is the purpose of willSet and didSet in Swift?
...ws conditional setting of an actual stored property
//True model data
var _test : Int = 0
var test : Int {
get {
return _test
}
set (aNewValue) {
//I've contrived some condition on which this property can be set
if (aNewValue != test) {
_test = aNewV...
VS Debug调试模式下内存泄露检测原理 - C/C++ - 清泛网 - 专注C/C++及内核技术
...T宏定义了malloc、realloc,如下:
#define malloc(s) _malloc_dbg(s, _NORMAL_BLOCK, __FILE__, __LINE__)
#define calloc(c, s) _calloc_dbg(c, s, _NORMAL_BLOCK, __FILE__, __LINE__)
#define realloc(p, s) _realloc_dbg(p, s, _NORMAL_BLOCK, __FILE__, __LINE__)
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Java: parse int value from a char
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System.out.println(c & 0b1111); // => '5' & 0b1111 => 0b0011_0101 & 0b0000_1111 => 5
// '0' & 0b1111 => 0b0011_0000 & 0b0000_1111 => 0
// '1' & 0b1111 => 0b0011_0001 & 0b0000_1111 => 1
// '2' & 0b1111 => 0b0011_0010 & 0b0000_1111 => 2
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Redirect stdout to a file in Python?
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@mgold or you can use sys.stdout = sys.__stdout__ to get it back.
– clemtoy
Jul 9 '15 at 12:52
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show 9 ...
Django 1.7 - makemigrations not detecting changes
... out) listed in the documentation:
python manage.py makemigrations your_app_label
The documentation does not make it obvious that you need to add the app label to the command, as the first thing it tells you to do is python manage.py makemigrations which will fail. The initial migration is don...
Calling closure assigned to object property directly
...sn't work on a StdClass.
Before PHP7, you'd have to implement the magic __call method to intercept the call and invoke the callback (which is not possible for StdClass of course, because you cannot add the __call method)
class Foo
{
public function __call($method, $args)
{
if(is_...
How update the _id of one MongoDB Document?
I want update an _id field of one document. I know it's not a really good pratice. But with some technical reason, I need update it. If I try to update it I get:
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python design patterns [closed]
...for their existence.
It's nothing more than
class Null(object):
def __init__(self, *args, **kwargs):
"Ignore parameters."
return None
def __call__(self, *args, **kwargs):
"Ignore method calls."
return self
def __getattr__(self, mname):
"Ignore...
How do I concatenate strings and variables in PowerShell?
... whitespace between $assoc.Id and " (et al). That is, option 1 gives you Id__-__Name__-__Owner (two spaces on each side of each -), but option 3 gives Id___-___Name___-___Owner (three spaces).
– ruffin
Dec 17 '14 at 15:10
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