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Are the days of passing const std::string & as a parameter over?
...f someone wants to hold on to it, they can. If they don't, oh well.
Is it more expensive? Yes; moving into a value is more expensive than using references. Is it less expensive than the copy? Not for small strings with SSO. Is it worth doing?
It depends on your use case. How much do you hate memor...
Entity Framework 4 Single() vs First() vs FirstOrDefault()
... query does not return zero or one items.
First() - when you expect one or more items to be returned by a query but you only want to access the first item in your code (ordering could be important in the query here). This will throw an exception if the query does not return at least one item.
FirstO...
Select first row in each GROUP BY group?
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Get unique values from a list in python [duplicate]
..., you should look for an ordered set implementation (see this question for more).
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What are C++ functors and their uses?
...bove, functors can be "customized" because they contain state, making them more flexible (If I wanted to use a function pointer, I'd have to write a function which added exactly 1 to its argument. The functor is general, and adds whatever you initialized it with), and they are also potentially more ...
How can I force a hard reload in Chrome for Android
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Is it safe to get values from a java.util.HashMap from multiple threads (no modification)?
...e time - but this effect is generally small. In exchange, you actually get more than what you asked for - not only can you safely publish one HashMap, you can store as many more not-modified HashMaps as you want to the same reference and be assured that all readers will see a safely published map.
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When to use an interface instead of an abstract class and vice versa?
...ss something like "a Doberman is a type of dog and every dog can walk" but more like "this thing can walk". Thank you
– aexl
Nov 9 '14 at 11:07
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How to export JavaScript array info to csv (on client side)?
...ows = [
["name1", "city1", "some other info"],
["name2", "city2", "more info"]
];
let csvContent = "data:text/csv;charset=utf-8,";
rows.forEach(function(rowArray) {
let row = rowArray.join(",");
csvContent += row + "\r\n";
});
or the shorter way (using arrow functions):
const ro...
Does Foreign Key improve query performance?
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@Kenny Often yes, but sometimes a better model costs more. Case in point: foreign keys cause more processing to happen, not less.
– Hans
Dec 6 '12 at 0:27
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