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How to shorten my conditional statements
...lyfill.
Short explanation of the ~ tilde shortcut:
Update: Since we now have the includes method, there's no point in using the ~ hack anymore. Just keeping this here for people that are interested in knowing how it works and/or have encountered it in other's code.
Instead of checking if th...
What part of Hindley-Milner do you not understand?
...σ), see overleaf.com/read/ddmnkzjtnqbd#/61990222
– SnowOnion
May 14 '18 at 14:02
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What does the `#` operator mean in Scala?
...le example:
class A {
class B
def f(b: B) = println("Got my B!")
}
Now let's try something with it:
scala> val a1 = new A
a1: A = A@2fa8ecf4
scala> val a2 = new A
a2: A = A@4bed4c8
scala> a2.f(new a1.B)
<console>:11: error: type mismatch;
found : a1.B
required: a2.B
...
Detect if a page has a vertical scrollbar?
...a solution that "just works" (cough). The algorithm I have come up with is now part of a plugin, jQuery.isInView, which exposes a .hasScrollbar method. Have a look at the source if you wish.
In a scenario where you are in full control of the page and don't have to deal with unknown CSS, using a pl...
How to invoke a Linux shell command from Java
...
@Narek. It should, but I don;'t know how csh handles arguments.
– KitsuneYMG
Sep 17 '09 at 12:38
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The input is not a valid Base-64 string as it contains a non-base 64 character
...w. Logic is to remove everything after , if data: is present. Bam. Working now.
– Maxime Rouiller
Jun 14 '16 at 13:14
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Applicatives compose, monads don't
...s -> let nmnt = ns >>= (return . f) in ???
we get this far, but now our layers are all jumbled up. We have an n (m (n t)), so we need to get rid of the outer n. As Alexandre C says, we can do that if we have a suitable
swap :: n (m t) -> m (n t)
to permute the n inwards and join it ...
How to use concerns in Rails 4
The default Rails 4 project generator now creates the directory "concerns" under controllers and models. I have found some explanations about how to use routing concerns, but nothing about controllers or models.
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When to use a Content Provider
... with other apps.
So even if you don't need any of these functionalities now, you might need them in future and its good to go the extra mile and implement them right now.
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SQL/mysql - Select distinct/UNIQUE but return all columns?
... Krakow
France Paris
France Marseille
Italy Milano
Now the query
SELECT country FROM locations
GROUP BY country
will result in:
--country--
France
Poland
Italy
However, the following query
SELECT country, city FROM locations
GROUP BY country
...throws an error in...