大约有 15,000 项符合查询结果（耗时：0.0272秒） [XML]
How do i find out what all symbols are exported from a shared object?
...
Addresses of names: 00037644
Entry Pt Ordn Name
0001FDA0 1 pcre_assign_jit_stack
000380B8 2 pcre_callout
00009030 3 pcre_compile
...
share
|
improve this answer
|
...
Creating the Singleton design pattern in PHP5
...ctor so nobody else can instantiate it
*
*/
private function __construct()
{
}
}
To use:
$fact = UserFactory::Instance();
$fact2 = UserFactory::Instance();
$fact == $fact2;
But:
$fact = new UserFactory()
Throws an error.
See http://php.net/manual/en/language.variable...
enum - getting value of enum on string conversion
...;>> member.name
'red'
>>> member.value
1
You could add a __str__ method to your enum, if all you wanted was to provide a custom string representation:
class D(Enum):
def __str__(self):
return str(self.value)
x = 1
y = 2
Demo:
>>> from enum import E...
Change auto increment starting number?
In MySQL, I have a table, and I want to set the auto_increment value to 5 instead of 1 . Is this possible and what query statement does this?
...
How can I implement a tree in Python?
...s easy to create. For example, a binary tree might be:
class Tree:
def __init__(self):
self.left = None
self.right = None
self.data = None
You can use it like this:
root = Tree()
root.data = "root"
root.left = Tree()
root.left.data = "left"
root.right = Tree()
root.right...
How can I read a function's signature including default argument values?
...
@darth_coder: In Python2, getargspec raises TypeError if the input is not recognized as a Python function -- that is, a function implemented in Python. In CPython, Exception.__init__ is implemented in C, hence the TypeError. You'll...
Python nested functions variable scoping [duplicate]
...When I run your code I get this error:
UnboundLocalError: local variable '_total' referenced before assignment
This problem is caused by this line:
_total += PRICE_RANGES[key][0]
The documentation about Scopes and Namespaces says this:
A special quirk of Python is that – if no global st...
Checking images for similarity with OpenCV
...e the L2 relative error between images.
double errorL2 = norm( A, B, CV_L2 );
// Convert to a reasonable scale, since L2 error is summed across all pixels of the image.
double similarity = errorL2 / (double)( A.rows * A.cols );
return similarity;
}
else {
//Images have a differen...
What does a type followed by _t (underscore-t) represent?
... with the Stack Overflow search or Google. What does a type followed by a _t mean? Such as
10 Answers
...
How to find the duration of difference between two dates in java?
...ce answer, I am facing one problem on your solution like I have two date 06_12_2017_07_18_02_PM and another one is 06_12_2017_07_13_16_PM, I am getting 286 seconds instead I should get only 46 seconds
– Panchal Amit
Dec 6 '17 at 14:14
...