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Why are hexadecimal numbers prefixed with 0x?
...an immediately tell the base (0 is the same in both bases),
it's mathematically sane (00005 == 05), and
no precious special characters are needed (as in #123).
When C was created from B, the need for hexadecimal numbers arose (the PDP-11 had 16-bit words) and all of the points above were still val...
Catching an exception while using a Python 'with' statement
... with open( "a.txt" ) as f :
print f.readlines()
except EnvironmentError: # parent of IOError, OSError *and* WindowsError where available
print 'oops'
If you want different handling for errors from the open call vs the working code you could do:
try:
f = open('foo.txt')
except IOE...
FixedThreadPool vs CachedThreadPool: the lesser of two evils
...an n threads might even result in your JRE being terminated because of OOM errors. So you should really distinguish between threads and work to do by those threads, how many work you are even able to process etc.
And that's the problem with CachedThreadPool: It doesn't make sense to queue up long ...
Apache两种工作模式区别及配置切换 - 更多技术 - 清泛网 - 专注C/C++及内核技术
Apache两种工作模式区别及配置切换1、Redhat Linux下查看apache版本号在Apache安装目录bin下，使用以下命令查看即可。使用命令：. httpd -v示例：2、查看Apache当前工作模...1、Redhat Linux下查看apache版本号
在Apache安装目录bin下，使用以下...
python exception message capturing
This doesn't seem to work, I get syntax error, what is the proper way of doing this for logging all kind of exceptions to a file
...
No 'Access-Control-Allow-Origin' - Node / Apache Port Issue
...-http-proxy and Vhosts Apache but not having much succes, please see full error and code below.
13 Answers
...
How do I create a link using javascript?
...document.querySelectorwill 'honor' your efforts with an Illegal invocation error the first time you use it. That's because the assignment just 'grabs' .querySelector (a ref to the class method). With .bind(... you'll also involve the context (here it's document) and you get an object method that'll...
How to detect iPhone 5 (widescreen devices)?
..._EPSILON )
The use of fabs with the epsilon is here to prevent precision errors, when comparing floating points, as pointed in the comments by H2CO3.
So from now on you can use it in standard if/else statements:
if( IS_IPHONE_5 )
{}
else
{}
Edit - Better detection
As stated by some people, th...
How can I add new array elements at the beginning of an array in Javascript?
...X
shift X X
Check out the MDN Array documentation. Virtually every language that has the ability to push/pop elements from an array will also have the ability to unshift/shift (sometimes called push_front/pop_front) elements, you should never have to implement these yourself.
A...
C++ STL Vectors: Get iterator from index?
...
Generally, you can use the same arithmetic with STL iterators than with pointers. They are designed to be exchangeable when using STL algorithms.
– Vincent Robert
Mar 22 '09 at 21:07
...