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Altering a column: null to not null
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How can I detect if a selector returns null?
... return this.length !== 0;
}
Used like:
$("#notAnElement").exists();
More explicit than using length.
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What are the benefits of Java's types erasure?
...hat is not interested in whether we can make the machine do something, but more whether we can reason that the machine will do something we actually want. Good reasoning is a proof. Proofs can be specified in formal notation or something less formal. Regardless of the specification language, they...
How do I replace text inside a div element?
...why textContent is a superior method to innerHTML: it's faster, safer, and more appropriate when not deliberately trying to insert HTML markup.
– CertainPerformance
Apr 16 '19 at 0:00
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Check list of words in another string [duplicate]
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What is the difference between Bower and npm?
...so a tree. It is just a special case. From WikiPedia: "In mathematics, and more specifically in graph theory, a tree is an undirected graph in which any two vertices are connected by exactly one path."
– Jørgen Fogh
Dec 25 '14 at 17:20
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Where does Java's String constant pool live, the heap or the stack?
...h the other objects created by the application. This change will result in more data residing in the main Java heap, and less data in the permanent generation, and thus may require heap sizes to be adjusted. Most applications will see only relatively small differences in heap usage due to this chang...
How do I find out which DOM element has the focus?
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@Rudie, @Stewart: I've built on your fiddle to create a more elaborate playground: jsfiddle.net/mklement/72rTF. You'll find that the only major browser (as of late 2012) that can actually focus such a div is Firefox 17, and only by tabbing to it. The types of elements that ALL maj...
How do you cast a List of supertypes to a List of subtypes?
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That is true, but it was more illustrative than factually correct
– Salandur
Dec 3 '13 at 21:13
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Group by in LINQ
...ere in the projection (p.car in this case) present for the given key.
For more on how GroupBy works, see my Edulinq post on the topic.
(I've renamed PersonID to PersonId in the above, to follow .NET naming conventions.)
Alternatively, you could use a Lookup:
var carsByPersonId = persons.ToLookup...