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Detect network connection type on Android
...er cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
return cm.getActiveNetworkInfo();
}
/**
* Check if there is any connectivity
* @param context
* @return
*/
public static boolean isConnected(Context context){
Networ...
Dictionary vs Object - which is more efficient and why?
...
Have you tried using __slots__?
From the documentation:
By default, instances of both old and new-style classes have a dictionary for attribute storage. This wastes space for objects having very few instance variables. The space consumption can ...
What does $_ mean in PowerShell?
...ich is called $PSItem in Powershell 3 and newer.
1,2,3 | %{ write-host $_ }
or
1,2,3 | %{ write-host $PSItem }
For example in the above code the %{} block is called for every value in the array. The $_ or $PSItem variable will contain the current value.
...
What are inline namespaces for?
...e header <vector> might have looked like this:
namespace std {
#if __cplusplus < 1997L // pre-standard C++
inline
#endif
namespace pre_cxx_1997 {
template <class T> __vector_impl; // implementation class
template <class T> // e.g. w/o allocator argumen...
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__)
...
Detecting request type in PHP (GET, POST, PUT or DELETE)
...
By using
$_SERVER['REQUEST_METHOD']
Example
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
// The request is using the POST method
}
For more details please see the documentation for the $_SERVER variable.
...
How to print out the method name and line number and conditionally disable NSLog?
...lot:
#ifdef DEBUG
# define DLog(fmt, ...) NSLog((@"%s [Line %d] " fmt), __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__)
#else
# define DLog(...)
#endif
// ALog always displays output regardless of the DEBUG setting
#define ALog(fmt, ...) NSLog((@"%s [Line %d] " fmt), __PRETTY_FUNCTION__, __LINE_...
How do I call setattr() on the current module?
...
import sys
thismodule = sys.modules[__name__]
setattr(thismodule, name, value)
or, without using setattr (which breaks the letter of the question but satisfies the same practical purposes;-):
globals()[name] = value
Note: at module scope, the latter is eq...
How do I spool to a CSV formatted file using SQLPLUS?
... numbers (avoid scientific notation on IDs)
spool myfile.csv
select table_name, tablespace_name
from all_tables
where owner = 'SYS'
and tablespace_name is not null;
Output will be like:
TABLE_PRIVILEGE_MAP ,SYSTEM
SYSTEM_PRIVILEGE_MAP ,S...
Circle line-segment collision detection algorithm?
...dy - dxh - dyk ) +
ex2 + ey2 -
2exh - 2eyk + h2 + k2 - r2 = 0
Finally,
t2( _d * _d ) + 2t( _e * _d - _d * _c ) + _e * _e - 2( _e*_c ) + _c * _c - r2 = 0
*Where _d is the vector d and * is the dot product.*
And then,
t2( _d * _d ) + 2t( _d * ( _e - _c ) ) + ( _e - _c ) * ( _e - _c ) - r2 = 0
Letting...