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In a storyboard, how do I make a custom cell for use with multiple controllers?
... registered. If it does, it instantiates an instance of that cell. This is composed of the following steps:
Look at the class of the cell, as defined in the cell's nib. Call [[CellClass alloc] initWithCoder:].
The -initWithCoder: method goes through and adds subviews and sets properties that were ...
Why do we need virtual functions in C++?
...l introduces some dynamic binding vs static and yes it is weird if you 're coming from languages like Java.
– peterchaula
Aug 6 '16 at 15:18
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Why are preprocessor macros evil and what are the alternatives?
...e_divide(b, a, x);
else printf("Something is not set...");
It actually becomes completely the wrong thing....
Replacement: real functions.
3) Macros have no namespace
If we have a macro:
#define begin() x = 0
and we have some code in C++ that uses begin:
std::vector<int> v;
... stu...
How does C compute sin() and other math functions?
...deps/ieee754/dbl-64/s_sin.c, look for __sin (double x).
This code is very complex. No one software algorithm is as fast as possible and also accurate over the whole range of x values, so the library implements several different algorithms, and its first job is to look at x and decide which algorith...
How do I use valgrind to find memory leaks?
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How to Run Valgrind
Not to insult the OP, but for those who come to this question and are still new to Linux—you might have to install Valgrind on your system.
sudo apt install valgrind # Ubuntu, Debian, etc.
sudo yum install valgrind # RHEL, CentOS, Fedora, etc.
Valgrind is re...
How to create the most compact mapping n → isprime(n) up to a limit N?
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How to find Unused Amazon EC2 Security groups
...upId' --output text | tr '\t' '\n' | sort | uniq
Then put it together and compare the 2 lists and see what's not being used from the master list:
comm -23 <(aws ec2 describe-security-groups --query 'SecurityGroups[*].GroupId' --output text | tr '\t' '\n'| sort) <(aws ec2 describe-instances ...
What are the rules about using an underscore in a C++ identifier?
It's common in C++ to name member variables with some kind of prefix to denote the fact that they're member variables, rather than local variables or parameters. If you've come from an MFC background, you'll probably use m_foo . I've also seen myFoo occasionally.
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In Java, when should I create a checked exception, and when should it be a runtime exception? [dupli
...xceptions being forgotten until they showed up in production (on agedwards.com), so we resolved to use checked exceptions exclusively.
At my current job, I find that there are many who are for Runtime exceptions in many or all cases.
Here's what I think: Using CheckedExceptions, I am forced at co...
To ARC or not to ARC? What are the pros and cons? [closed]
...old code. It is not garbage collection. It has no GC runtime overhead. The compiler inserts retains and releases in all the places you should have anyway. But it's smarter than you and can optimize out the ones that aren't actually needed (just like it can unroll loops, eliminate temporary variables...