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How to check that an object is empty in PHP?
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You can cast to an array and then check if it is empty or not
$arr = (array)$obj;
if (!$arr) {
// do stuff
}
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How to cast Object to its actual type?
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Nevermind, found as for typecasting and type(of: ClassName) function to check instance type.
– Nagendra Rao
Apr 22 '17 at 20:34
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Difference between Covariance & Contra-variance
...vide so-called “multiple dispatch” or multi methods (this is basically selecting function overloads at run time, e.g. with CLOS) or get the desired effect by using dynamic typing.
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What does “dereferencing” a pointer mean?
...he pointer may be relative to some specific memory area, which the CPU may select based on CPU "segment" registers or some manner of segment id encoded in the bit-pattern, and/or looking in different places depending on the machine code instructions using the address.
For example, an int* properly ...
Can I assume (bool)true == (int)1 for any C++ compiler?
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Yes. The casts are redundant. In your expression:
true == 1
Integral promotion applies and the bool value will be promoted to an int and this promotion must yield 1.
Reference: 4.7 [conv.integral] / 4: If the source type is bool....
Pass An Instantiated System.Type as a Type Parameter for a Generic Class
...amic is still rooted to a strongly typed language the run time binder will select the appropriate Markdown method. If there is no exact type matches, it will look for an object parameter method and if neither match a runtime binder exception will be raised alerting that no method matches.
The obvio...
What is the concept of erasure in generics in Java?
...ain just talks in terms of java.lang.Object - the compiler generates extra casts where necessary. At execution time, a List<String> and a List<Date> are exactly the same; the extra type information has been erased by the compiler.
Compare this with, say, C#, where the information is re...
Entity Framework - Include Multiple Levels of Properties
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For EF 6
using System.Data.Entity;
query.Include(x => x.Collection.Select(y => y.Property))
Make sure to add using System.Data.Entity; to get the version of Include that takes in a lambda.
For EF Core
Use the new method ThenInclude
query.Include(x => x.Collection)
.ThenIncl...
How do I convert a string to enum in TypeScript?
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So we can use typecast: let s = "Green"; let typedColor = <keyof typeof Color> s;
– SergeyT
Jun 8 '17 at 13:06
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how to convert array values from string to int?
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intval() is less performant than (int) cast. So better use another solution with (int). see Method 3 here
– Fabian Picone
Apr 19 '16 at 7:24
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