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How do I check in JavaScript if a value exists at a certain array index?
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Conceptually, arrays in JavaScript contain array.length elements, starting with array[0] up until array[array.length - 1]. An array element with index i is defined to be part of the array if i is between 0 and array.length - 1 inclu...
Why can I not push_back a unique_ptr into a vector?
...to a local variable. The lifetime of a local variable is managed automatically: local variables are destroyed when the block ends (e.g., when the function returns, in this case). You need to dynamically allocate the object:
std::unique_ptr<int> ptr(new int(1));
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Is there a performance difference between i++ and ++i in C++?
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However, if i is an instance of a C++ class, then i++ and ++i are making calls to one of the operator++ functions. Here's a standard pair of these functions:
Foo& Foo::operator++() // called for ++i
{
this->data += 1;
return *this;
}
Foo Foo::operator++(int ignored_dummy_value) ...
Pass an array of integers to ASP.NET Web API?
...iptor.GetConverter(elementType);
var values = Array.ConvertAll(s.Split(new[] { ","},StringSplitOptions.RemoveEmptyEntries),
x => { return converter.ConvertFromString(x != null ? x.Trim() : x); });
var typedValues = Array.CreateInstance(elementT...
How do I find out which keystore was used to sign an app?
...ture algorithm name: SHA1withRSA
Then use the keytool again to print out all the aliases of your signing keystore:
keytool -list -keystore my-signing-key.keystore
You will get a list of aliases and their certificate fingerprint:
android_key, Jan 23, 2010, PrivateKeyEntry,
Certificate fingerpri...
Where to store global constants in an iOS application?
...sets of constants to include before #include-ing the constants file (stops all those "defined but not used" compiler warnings).
– user244343
Aug 19 '11 at 2:26
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What's the difference between dynamic (C# 4) and var?
...iteLine(s.Length);
and
string s = "abc";
Console.WriteLine(s.Length);
All that happened was that the compiler figured out that s must be a string (from the initializer). In both cases, it knows (in the IL) that s.Length means the (instance) string.Length property.
dynamic is a very different b...
When to use EntityManager.find() vs EntityManager.getReference() with JPA
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I usually use getReference method when i do not need to access database state (I mean getter method). Just to change state (I mean setter method). As you should know, getReference returns a proxy object which uses a powerful featu...
Unsupported major.minor version 52.0 [duplicate]
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"J2SE" was only used till Java 1.5 and is nowadays called "Java SE", see en.wikipedia.org/wiki/Java_Platform,_Standard_Edition
– Tim Büthe
Sep 6 '16 at 14:38
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JavaScript chop/slice/trim off last character in string
...viously using the substring version. Thanks!
– Matt Ball
Apr 13 '10 at 14:09
33
forgive me if I'm...