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Using sections in Editor/Display templates
I want to keep all of my JavaScript code in one section; just before the closing body tag in my master layout page and just wondering the best to go about it, MVC style.
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Cartesian product of multiple arrays in JavaScript
...S
Original 2017 Answer: 2-line answer with vanilla JS:
(see updates below)
All of the answers here are overly complicated, most of them take 20 lines of code or even more.
This example uses just two lines of vanilla JavaScript, no lodash, underscore or other libraries:
let f = (a, b) => [].concat...
In pure functional languages, is there an algorithm to get the inverse function?
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In some cases, yes! There's a beautiful paper called Bidirectionalization for Free! which discusses a few cases -- when your function is sufficiently polymorphic -- where it is possible, completely automatically to derive an inverse function. (It also discusses what makes...
Troubleshooting “Illegal mix of collations” error in mysql
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This is generally caused by comparing two strings of incompatible collation or by attempting to select data of different collation into a combined column.
The clause COLLATE allows you to specify the collation used in the query.
For exa...
How to define “type disjunction” (union types)?
...str")
case _: Int => println("int")
}
}
And that's it. You can call foo(5) or foo("abc"), and it will work, but try foo(true) and it will fail. This could be side-stepped by the client code by creating a StringOrInt[Boolean], unless, as noted by Randall below, you make StringOrInt a seale...
How to deep copy a list?
... don't make a deep copy using list() (Both list(...) and testList[:] are shallow copies).
You use copy.deepcopy(...) for deep copying a list.
deepcopy(x, memo=None, _nil=[])
Deep copy operation on arbitrary Python objects.
See the following snippet -
>>> a = [[1, 2, 3], [4, 5, 6]]...
How to avoid 'cannot read property of undefined' errors?
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Catching all exceptions without re-throwing is bad, and generally using exceptions as part of the expected flow of execution is also not great -- even though in this case it's pretty well contained.
– hugo
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What's the difference between django OneToOneField and ForeignKey?
...Guide to Django:
OneToOneField
A one-to-one relationship. Conceptually, this is similar to a ForeignKey with unique=True, but the "reverse" side of the relation will directly return a single object.
In contrast to the OneToOneField "reverse" relation, a ForeignKey "reverse" relation retur...
Getting attributes of a class
...gt;> inspect.getmembers(MyClass, lambda a:not(inspect.isroutine(a)))
[('__class__', type),
('__dict__',
<dictproxy {'__dict__': <attribute '__dict__' of 'MyClass' objects>,
'__doc__': None,
'__module__': '__main__',
'__weakref__': <attribute '__weakref__' of 'MyClass' obje...
Nested or Inner Class in PHP
...There are several compelling reasons for using them:
It is a way of logically grouping classes that are only used in one place.
If a class is useful to only one other class, then it is logical to
relate and embed it in that class and keep the two together.
It increases encapsulation.
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