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Is there a regular expression to detect a valid regular expression?
Is it possible to detect a valid regular expression with another regular expression? If so please give example code below.
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Where is shared_ptr?
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Georg Fritzsche
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answered May 27 '10 at 3:06
YeenFeiYeenFei
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How to check whether a file or directory exists?
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Denys SéguretDenys Séguret
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Convert Python dictionary to JSON array
...ne 1, in <module>
File "/usr/lib/python2.7/json/__init__.py", line 328, in loads
return _default_decoder.decode(s)
File "/usr/lib/python2.7/json/decoder.py", line 365, in decode
obj, end = self.raw_decode(s, idx=_w(s, 0).end())
File "/usr/lib/python2.7/json/decoder.py", line 381,...
Python unit test with base and sub class
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Just to clarify Ian Clelland's remark so that it will be clearer for people like me: if you add setUp and tearDown methods to CommonTests c...
'float' vs. 'double' precision
...question of how many digits can be stored in a binary integer: an unsigned 32 bit integer can store integers with up to 32 bits, which doesn't precisely map to any number of decimal digits: all integers of up to 9 decimal digits can be stored, but a lot of 10-digit numbers can be stored as well.
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Java List.add() UnsupportedOperationException
I try to add objects to a List<String> instance but it throws an UnsupportedOperationException .
Does anyone know why?
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C++中判断文件、目录是否存在的几种方法 - C/C++ - 清泛网 - 专注C/C++及内核技术
...系统的一些函数，但这种方法稍微显得复杂一些。
WIN32_FIND_DATA wfd;
bool rValue = false;
HANDLE hFind = FindFirstFile(strPath.c_str(), &wfd);
if ((hFind != INVALID_HANDLE_VALUE) && (wfd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY))
{
std::cout << "this file exists" << ...
Explain the use of a bit vector for determining if all characters are unique
... between them:
Size. int has fixed size, usually 4 bytes which means 8*4=32 bits (flags). Bit vector usually can be of different size or you should specify the size in constructor.
API. With bit vectors you will have easier to read code, probably something like this:
vector.SetFlag(4, true); // s...
What is Castle Windsor, and why should I care?
I'm a long-time Windows developer, having cut my teeth on win32 and early COM. I've been working with .NET since 2001, so I'm pretty fluent in C# and the CLR. I'd never heard of Castle Windsor until I started participating in Stack Overflow. I've read the Castle Windsor "Getting Started" guide, b...