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Objective-C declared @property attributes (nonatomic, copy, strong, weak)
...(can be accessed from multiple threads without botching of data)
Copy
copy is required when the object is mutable. Use this if you need the value of the object as it is at this moment, and you don't want that value to reflect any changes made by other owners of the object. You will need to release t...
How does free know how much to free?
...o not have to pass the size to the free function. Why not, and can I use this same technique in my own functions to save me from needing to cart around the extra variable of the array's length?
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What is the max size of localStorage values?
... need to be stringified (stored as JSON-string) before they can be stored, is there a defined limitation regarding the length of the values.
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Why does base64 encoding require padding if the input length is not divisible by 3?
What is the purpose of padding in base64 encoding. The following is the extract from wikipedia:
3 Answers
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How does facebook, gmail send the real time notification?
I have read some posts about this topic and the answers are comet, reverse ajax, http streaming, server push, etc.
5 Answer...
Where is C not a subset of C++? [closed]
I read in a lot of books that C is a subset of C++.
12 Answers
12
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Difference between char* and const char*?
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char* is a mutable pointer to a mutable character/string.
const char* is a mutable pointer to an immutable character/string. You cannot change the contents of the location(s) this pointer points to. Also, compilers are required to...
How to count the number of occurrences of an element in a List
I have an ArrayList , a Collection class of Java, as follows:
22 Answers
22
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Why are these constructs using pre and post-increment undefined behavior?
...s are syntactically valid but you can't predict the behavior when the code is run.
As far as I know, the standard doesn't explicitly say why the concept of undefined behavior exists. In my mind, it's simply because the language designers wanted there to be some leeway in the semantics, instead of i...
Why would iterating over a List be faster than indexing through it?
Reading the Java documentation for the ADT List it says:
5 Answers
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