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Purpose of returning by const value? [duplicate]
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In the hypothetical situation where you could perform a potentially expensive non-const operation on an object, returning by const-value prevents you from accidentally calling this operation on a temporary. Imagine that + returned a non-const value, and you could write:
(a + b).expensiv...
How do I determine the size of my array in C?
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It should be the case with all compilers, since the results of sizeof is defined as a compile-time constant.
– Mark Harrison
Sep 22 '13 at 5:39
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How to pass parameters correctly?
... Are there any best practices of how to send parameters in C++ because I really find it, let's say, not trivial
If your function needs to modify the original object being passed, so that after the call returns, modifications to that object will be visible to the caller, then you should pass by lva...
Why use Object.prototype.hasOwnProperty.call(myObj, prop) instead of myObj.hasOwnProperty(prop)?
...y reference.
And since we are at it, why do we define this function at all?
See above.
Is it
just a question of shortcuts and local caching of property access for
(slight) performance gains...
It may make it quicker in theory, as the [[Prototype]] chain doesn't have to be followed, ...
Installation error: INSTALL_PARSE_FAILED_MANIFEST_MALFORMED?
I am developing a small application that lists all the applications present/ installed on the android device. But I'm getting the below error while i'm trying to run the code.
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How to set variables in HIVE scripts
...em variables as well, so you can reference ${env:USER} for example.
To see all the available variables, from the command line, run
% hive -e 'set;'
or from the hive prompt, run
hive> set;
Update:
I've started to use hivevar variables as well, putting them into hql snippets I can include from hi...
Shorthand way for assigning a single field in a record, while copying the rest of the fields?
...e's a nice way of updating record fields. In GHCi you can do --
> data Foo = Foo { a :: Int, b :: Int, c :: String } -- define a Foo
> let foo = Foo { a = 1, b = 2, c = "Hello" } -- create a Foo
> let updateFoo x = x { c = "Goodbye" } -- function to update Foos
> ...
Block Declaration Syntax List
...at this is distinct from "Blocks as Parameters"; in this instance, you're calling a method that wants a block argument with an anonymous block. If you have already declared a block variable, it is sufficient to pass the variable name as the argument.
[someObject doSomethingWithBlock: ^return_type (...
What is the use of “ref” for reference-type variables in C#?
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You can change what foo points to using y:
Foo foo = new Foo("1");
void Bar(ref Foo y)
{
y = new Foo("2");
}
Bar(ref foo);
// foo.Name == "2"
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What is the “assert” function?
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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...