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What is the “assert” function?
...
assert will terminate the program (usually with a message quoting the assert statement) if its argument turns out to be false. It's commonly used during debugging to make the program fail more obviously if an unexpected condition occurs.
For example:
assert(len...
How to use range-based for() loop with std::map?
...t;< std::endl;
}
if you don't plan on modifying the values.
In C++11 and C++14, you can use enhanced for loops to extract out each pair on its own, then manually extract the keys and values:
for (const auto& kv : myMap) {
std::cout << kv.first << " has value " << kv....
Direct casting vs 'as' operator?
... tend to almost never use 2 since if something is not the right type, I usually expect an exception to occur. I have only seen a need for this return-null type of functionality with badly designed libraries which use error codes (e.g. return null = error, instead of using exceptions).
3 is not a ca...
How to see which commits in one branch aren't in the other?
...rence. For example, if you have two branches, A and B, a usual way to list all commits on only one side of them is with --left-right, like the example above in the description of that option. It however shows the commits that were cherry-picked from the other branch (for example, "3rd on b" may be c...
process.env.NODE_ENV is undefined
...e default value should be 'development'. How is this value dynamically set and where is it set initially?
12 Answers
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Detect permission of camera in iOS
...se if(authStatus == AVAuthorizationStatusRestricted){
// restricted, normally won't happen
} else if(authStatus == AVAuthorizationStatusNotDetermined){
// not determined?!
[AVCaptureDevice requestAccessForMediaType:mediaType completionHandler:^(BOOL granted) {
if(granted){
NSLog(@"Gr...
What is the difference between a.getClass() and A.class in Java?
...getClass() will return the B class.
A.class evaluates to the A class statically, and is used for other purposes often related to reflection.
In terms of performance, there may be a measurable difference, but I won't say anything about it because in the end it is JVM and/or compiler dependent.
T...
What do the return values of node.js process.memoryUsage() stand for?
... Scheme first.
A running program is always represented through some space allocated in memory. This space is called Resident Set. V8 uses a scheme similar to the Java Virtual Machine and divides the memory into segments:
Code: the actual code being executed
Stack: contains all value types (prim...
Java naming convention for static final variables [duplicate]
...mation regarding the naming convention for constants. But in reality, it's all a matter of preference.
The names of constants in interface types should be, and final
variables of class types may conventionally be, a sequence of one or
more words, acronyms, or abbreviations, all uppercase, ...
How to replace a character with a newline in Emacs?
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C-q is really quote-insert which quotes the next character.
– Joe Casadonte
Mar 5 '09 at 2:17
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