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Why use ICollection and not IEnumerable or List on many-many/one-many relationships?
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Usually what you choose will depend on which methods you need access to. In general - IEnumerable<> (MSDN: http://msdn.microsoft.com/en-us/library/system.collections.ienumerable.aspx) for a list of objects that only needs ...
What is the real overhead of try/catch in C#?
... to make here:
Firstly, there is little or NO performance penalty in actually having try-catch blocks in your code. This should not be a consideration when trying to avoid having them in your application. The performance hit only comes into play when an exception is thrown.
When an exception is th...
insert multiple rows via a php array into mysql
...like you might be running into string-handling problems in PHP, which is really an algorithm problem, not a language one. Basically, when working with large strings, you want to minimize unnecessary copying. Primarily, this means you want to avoid concatenation. The fastest and most memory efficient...
Is it good style to explicitly return in Ruby?
...d
Was this meant to be a function that returned a value, or not? It's really hard to say what the developer meant, as it both assigns the instance variable, AND returns the value assigned as well.
Suppose much later, another programmer (perhaps not that familiar with how Ruby does returns based ...
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...
NSDictionary - Need to check whether dictionary contains key-value pair or not
...uldn't we mistakenly think that the key isn't present in the dictionary at all?
– jbx72487
Feb 1 '13 at 18:51
13
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Difference between a “coroutine” and a “thread”?
...the baton among each other more fluidly).
Threads are (at least conceptually) a form of concurrent processing: multiple threads may be executing at any given time. (Traditionally, on single-CPU, single-core machines, that concurrency was simulated with some help from the OS -- nowadays, since so...
Load view from an external xib file in storyboard
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Isn't it that loadNibNamed calls init(coder:)? I have a crash trying to adapt your approach.
– Fishman
Nov 14 '16 at 9:15
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NSUserDefaults - How to tell if a key exists
I'm working on a small iPhone app, and I am using NSUserDefaults as my data persistence. It only has to keep track of a few things, such as some names and some numbers so I figure I might as well keep it simple.
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How to convert a number to string and vice versa in C++
...o-number conversion and vice-versa are built in into the standard library. All the following functions are present in <string> (as per paragraph 21.5).
string to numeric
float stof(const string& str, size_t *idx = 0);
double stod(const string& str, size_t *id...