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Why can I change value of a constant in javascript
...nst x = {};
x.foo = 'bar';
console.log(x); // {foo : 'bar'}
x.foo = 'bar2';
console.log(x); // {foo : 'bar2'}
and this:
const y = [];
y.push('foo');
console.log(y); // ['foo']
y.unshift("foo2");
console.log(y); // ['foo2', 'foo']
y.pop();
console.log(y); // ['foo2']
but neither of...
Is there a good reason I see VARCHAR(255) used so often (as opposed to another length)?
...tiple courses, books, and jobs, I have seen text fields defined as VARCHAR(255) as kind of the default for "shortish" text. Is there any good reason that a length of 255 is chosen so often, other than being a nice round number ? Is it a holdout from some time in the past when there was a good rea...
Set operations (union, intersection) on Swift array?
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Yes, Swift has the Set class.
let array1 = ["a", "b", "c"]
let array2 = ["a", "b", "d"]
let set1:Set<String> = Set(array1)
let set2:Set<String> = Set(array2)
Swift 3.0+ can do operations on sets as:
firstSet.union(secondSet)// Union of two sets
firstSet.intersection(secondSet)...
LINQ Using Max() to select a single row
...
233
I don't see why you are grouping here.
Try this:
var maxValue = table.Max(x => x.Status)
...
how to create a Java Date object of midnight today and midnight tomorrow?
...pare against dates from today at 00:00am (midnight early this morning) to 12:00pm (midnight tonight).
19 Answers
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Find object by id in an array of JavaScript objects
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How to split the name string in mysql?
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I've seperated this answer into two(2) methods. The first method will separate your fullname field into first, middle, and last names. The middle name will show as NULL if there is no middle name.
SELECT
SUBSTRING_INDEX(SUBSTRING_INDEX(fullname, ' ', 1), ...
Which maven dependencies to include for spring 3.0?
... do my first project with Spring 3.0 (and maven). I have been using Spring 2.5 (and primer versions) in quite some projects. Nevertheless I am kinda confused, what modules I have to define as dependencies in my pom.xml. I just want to use the core container functions (beans, core, context, el).
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Does anyone know what the new Exit icon is used for when editing storyboards using Xcode 4.5?
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Dmitry Minkovsky
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answered Sep 25 '12 at 0:50
Cal SCal S
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Is there a reason that Swift array assignment is inconsistent (neither a reference nor a deep copy)?
...), so the question no longer applies. The following answer applied to beta 2:
It's for performance reasons. Basically, they try to avoid copying arrays as long as they can (and claim "C-like performance"). To quote the language book:
For arrays, copying only takes place when you perform an ac...