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Scala: Abstract types vs generics
...you have abstract methods, but you can't pass a method as a parameter.
You don't have abstract fields, but you can pass a value as a parameter.
And similarly you don't have abstract type members, but you can specify a type as a parameter.
So in Java you also have all three of these, but there's a di...
Is it possible to focus on a using JavaScript focus() function?
...
window.location.hash = '#tries';
This will scroll to the element in question, essentially "focus"ing it.
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Extract a dplyr tbl column as a vector
...te(y))) deparse(substitute(y)) else y, drop = FALSE][[1]]}
This lets you do either of these:
iris2 %>% pull('Species')
iris2 %>% pull(Species)
iris2 %>% pull(5)
Resulting in...
[1] 21.0 21.0 22.8 21.4 18.7 18.1 14.3 24.4 22.8 19.2 17.8 16.4 17.3 15.2 10.4 10.4 14.7 32.4 30.4 33.9 21....
Attach parameter to button.addTarget action in Swift
...meters in addTarget:.One alternative is set the tag property of button and do work based on the tag.
button.tag = 5
button.addTarget(self, action: "buttonClicked:",
forControlEvents: UIControlEvents.TouchUpInside)
Or for Swift 2.2 and greater:
button.tag = 5
button.addTarget(self,action:#se...
How to modify existing, unpushed commit messages?
...mmit messages or small corrections more cumbersome to enter.
Make sure you don't have any working copy changes staged before doing this or they will get committed too. (Unstaged changes will not get committed.)
Changing the message of a commit that you've already pushed to your remote branch
If you'...
Optional Methods in Java Interface
...interface:
What the Java language can check. This pretty much just boils down to: is there some implementation for each of the methods?
Actually fulfilling the contract. That is, does the implementation do what the documentation in the interface says it should?
Well written interfaces will includ...
jQuery - setting the selected value of a select control via its text description
...le $('select').val('Two') will select the second option in 1.3.x, but will do nothing in 1.4.x.
– Crescent Fresh
Mar 3 '10 at 19:34
18
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Javascript add leading zeroes to date
...e answer that @Aleross provides below? It is not immediately clear what it does versus the pad function which is explicitly clear.
– claudio
Oct 29 '13 at 20:37
2
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How to post data to specific URL using WebClient in C#
...problem is that the garbage collector may take an arbitrarily long time to do so, since it does not account for unmanaged resources when making collection decisions. High-value resources must be cleaned up as soon as possible. For example, leaving open an unneeded file handle could block the file ...
How to check if a file exists in the Documents directory in Swift?
How to check if a file exists in the Documents directory in Swift ?
12 Answers
12
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