大约有 40,000 项符合查询结果(耗时:0.0525秒) [XML]

https://stackoverflow.com/ques... 

Why does `a == b or c or d` always evaluate to True?

...r is more literal minded. if name == "Kevin" or "Jon" or "Inbar": is logically equivalent to: if (name == "Kevin") or ("Jon") or ("Inbar"): Which, for user Bob, is equivalent to: if (False) or ("Jon") or ("Inbar"): The or operator chooses the first argument with a positive truth value: if ("Jon")...
https://stackoverflow.com/ques... 

Setting environment variables for accessing in PHP when using Apache

I have a Linux environment and I have a PHP Web Application that conditionally runs based on environment variables using getenv in PHP. I need to know how these environment variables need to be set for the application to work correctly. I am not sure how to set this up on Apache. ...
https://stackoverflow.com/ques... 

Combine --user with --prefix error with setup.py install

...me workaround: pip install --user --install-option="--prefix=" <package_name> or python setup.py install --user --prefix= Note that there is no text (not even whitespace) after the =. Do not forget the --user flag. Installing multiple packages: Create ~/.pydistutils.cfg (or equivalent...
https://stackoverflow.com/ques... 

Can I list-initialize a vector of move-only type?

...nitializer list elements in the current revision of the language. Specifically, we have: typedef const E& reference; typedef const E& const_reference; typedef const E* iterator; typedef const E* const_iterator; const E* begin() const noexcept; // first element const E* end() const noexce...
https://stackoverflow.com/ques... 

How to launch jQuery Fancybox on page load?

..."text/javascript"> $(document).ready(function() { $("#hidden_link").fancybox().trigger('click'); }); </script> share | improve this answer | follow ...
https://stackoverflow.com/ques... 

Nullable Foreign Key bad practice?

... read. Only if you know better than Chris Date "what first normal form really means". If x and y are both nullable, and indeed in some row x and y are both null, then WHERE x=y does not yield true. This proves beyond reasonable doubt that null is not a value (because any real value is always equ...
https://stackoverflow.com/ques... 

Node.js: printing to console without a trailing newline?

...ered May 27 '11 at 20:51 onteria_onteria_ 57.1k66 gold badges6363 silver badges6060 bronze badges ...
https://stackoverflow.com/ques... 

How do PHP sessions work? (not “how are they used?”)

...on files are usually stored in, say, /tmp/ on the server, and named sess_{session_id} . I have been looking at the contents and cannot figure out how they really work. ...
https://stackoverflow.com/ques... 

reference assignment is atomic so why is Interlocked.Exchange(ref Object, Object) needed?

In my multithreaded asmx web service I had a class field _allData of my own type SystemData which consists of few List<T> and Dictionary<T> marked as volatile . The system data ( _allData ) is refreshed once in a while and I do it by creating another object called newData and fill...
https://stackoverflow.com/ques... 

Mutex example / tutorial? [closed]

... The first person to catch the door-handle of the booth, is the one who is allowed to use the phone. He has to keep holding on to the handle of the door as long as he uses the phone, otherwise someone else will catch hold of the handle, throw him out and talk to his wife :) There's no queue system a...