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What do two question marks together mean in C#?
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@Gusdor ?? is left associative, so a ?? b ?? c ?? d is equivalent to ((a ?? b) ?? c ) ?? d. "The assignment operators and the ternary operator (?:) are right associative. All other binary operators are left associative." Source: ...
What is 'Currying'?
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Currying is when you break down a function that takes multiple arguments into a series of functions that each take only one argument. Here's an example in JavaScript:
function add (a, b) {
return a + b;
}
add(3, 4); // returns 7
This is a funct...
What is the difference between IQueryable and IEnumerable?
...e<T> extends the IEnumerable<T> interface, so anything you can do with a "plain" IEnumerable<T>, you can also do with an IQueryable<T>.
IEnumerable<T> just has a GetEnumerator() method that returns an Enumerator<T> for which you can call its MoveNext() method to...
What are all the uses of an underscore in Scala?
...estion: " Can you name all the uses of “_”? ". Can you? If yes, please do so here. Explanatory examples are appreciated.
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javac is not recognized as an internal or external command, operable program or batch file [closed]
...ve not installed Java correctly. Finalizing the installation of Java on Windows requires some manual steps. You must always perform these steps after installing Java, including after upgrading the JDK.
Environment variables and PATH
(If you already understand this, feel free to skip the next three...
Is there a reason that we cannot iterate on “reverse Range” in ruby?
...efined by its start and end, not by its contents. "Iterating" over a range doesn't really make sense in a general case. Consider, for example, how you would "iterate" over the range produced by two dates. Would you iterate by day? by month? by year? by week? It's not well-defined. IMO, the fact that...
When to use Vanilla JavaScript vs. jQuery?
...javascript, instead of jQuery, that actually enable you to write less and do ... well the same amount. And may also yield performance benefits.
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How to get last N records with activerecord?
..., so you could let ruby sort it at at that time. (ie. records.reverse.each do ..)
– Dan McNevin
Jan 7 '09 at 14:25
Alt...
Eloquent Collection: Counting and Detect Empty
...ch will always return true.
To determine if there are any results you can do any of the following:
if ($result->first()) { }
if (!$result->isEmpty()) { }
if ($result->count()) { }
if (count($result)) { }
You could also use ->first() instead of ->get() on the query builder which w...
What uses are there for “placement new”?
...to construct an object in memory that's already allocated.
You may want to do this for optimization when you need to construct multiple instances of an object, and it is faster not to re-allocate memory each time you need a new instance. Instead, it might be more efficient to perform a single alloc...