大约有 43,738 项符合查询结果（耗时：0.0378秒） [XML]
UnboundLocalError on local variable when reassigned after first use
...s to them from inside or outside the function. If a variable is assigned within a function, it is treated by default as a local variable. Therefore, when you uncomment the line you are trying to reference the local variable c before any value has been assigned to it.
If you want the variable c to...
C++ - passing references to std::shared_ptr or boost::shared_ptr
If I have a function that needs to work with a shared_ptr , wouldn't it be more efficient to pass it a reference to it (so to avoid copying the shared_ptr object)?
What are the possible bad side effects?
I envision two possible cases:
...
What XML parser should I use in C++? [closed]
... documents that I need to parse and/or I need to build XML documents and write them to text (either files or memory). Since the C++ standard library does not have a library for this, what should I use?
...
Can a local variable's memory be accessed outside its scope?
...
How can it be? Isn't the memory of a local variable inaccessible outside its function?
You rent a hotel room. You put a book in the top drawer of the bedside table and go to sleep. You check out the next morning, but "forget" to g...
To ARC or not to ARC? What are the pros and cons? [closed]
I've yet to use ARC, since the majority of the code in the project I'm working on at the moment was written pre-iOS 5.0.
6...
Is it good practice to NULL a pointer after deleting it?
...be that doing so just masks double delete bugs and leaves them unhandled.
It's best to not have double delete bugs, obviously, but depending on ownership semantics and object lifecycles, this can be hard to achieve in practice. I prefer a masked double delete bug over UB.
Finally, a sidenote regar...
Is it good style to explicitly return in Ruby?
Coming from a Python background, where there is always a "right way to do it" (a "Pythonic" way) when it comes to style, I'm wondering if the same exists for Ruby. I've been using my own style guidelines but I'm thinking about releasing my source code, and I'd like it to adhere to any unwritten rule...
int a[] = {1,2,}; Weird comma allowed. Any particular reason?
Maybe I am not from this planet, but it would seem to me that the following should be a syntax error:
20 Answers
...
Is a memory leak created if a MemoryStream in .NET is not closed?
...
If something is Disposable, you should always Dispose it. You should be using a using statement in your bar() method to make sure ms2 gets Disposed.
It will eventually get cleaned up by the garbage collector, but it is always good practice to call Dispose. If you run FxCop on y...
Must Dependency Injection come at the expense of Encapsulation?
...nd correctly, the typical mechanism for Dependency Injection is to inject either through a class' constructor or through a public property (member) of the class.
...