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Make $JAVA_HOME easily changable in Ubuntu [closed]
In Ubuntu, I'd like to switch my JAVA_HOME environment variable back and forth between Java 5 and 6.
8 Answers
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Scala: join an iterable of strings
...,"): String = list match { case head :: tail => tail.foldLeft(head)(_ + delim + _) case Nil => "" }
– Davos
Jul 11 '17 at 14:37
2
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CSS: Change image src on img:hover
... <img src="https://cdn4.iconfinder.com/data/icons/imoticons/105/imoticon_15-128.png" />
<img src="https://cdn4.iconfinder.com/data/icons/imoticons/105/imoticon_12-128.png" />
</a>
CSS
a img:last-child {
display: none;
}
a:hover img:last-child {
display: block;
}
a:ho...
AsyncProcedures异步过程扩展 · App Inventor 2 中文网
...行耗时过程
when Button1.Click
do
// 异步调用耗时过程
call AsyncProcedures1.RunProcedure LongRunningProcess
// 异步过程完成后的回调
when AsyncProcedures1.ProcedureCompleted
do
show notification "异步过程执行完成"
带参数的异步过程
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Cell spacing in UICollectionView
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This is a much better answer. Take a look at the callbacks you can adjust in the UICollectionViewDelegateFlowLayout and you can see how this can be tweaked.
– cynistersix
Dec 17 '14 at 2:52
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How to find index of list item in Swift?
...B = arr.indexOf("b") // 1
let indexOfD = arr.indexOf("d") // nil
Additionally, finding the first element in an array fulfilling a predicate is supported by another extension of CollectionType:
let arr2 = [1,2,3,4,5,6,7,8,9,10]
let indexOfFirstGreaterThanFive = arr2.indexOf({$0 > 5}) // 5
let i...
Convert a String representation of a Dictionary to a dictionary?
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Starting in Python 2.6 you can use the built-in ast.literal_eval:
>>> import ast
>>> ast.literal_eval("{'muffin' : 'lolz', 'foo' : 'kitty'}")
{'muffin': 'lolz', 'foo': 'kitty'}
This is safer than using eval. As its own docs say:
>>> help(ast.literal_e...
Avoiding memory leaks with Scalaz 7 zipWithIndex/group enumeratees
...ess1.chunk(4)
pipe process1.fold(0L) {
(c, vs) => c + vs.map(_._1.length.toLong).sum
}).runLast.run
This should work with any value for the n parameter (provided you're willing to wait long enough) -- I tested with 2^14 32MiB arrays (i.e., a total of half a TiB of memory allocated ...
SQL Switch/Case in 'where' clause
...statement exits after a condition is met - but the OR syntax will evaluate all the possibilities
– tember
May 12 '15 at 18:27
1
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How to convert string representation of list to a list?
... ast
>>> x = u'[ "A","B","C" , " D"]'
>>> x = ast.literal_eval(x)
>>> x
['A', 'B', 'C', ' D']
>>> x = [n.strip() for n in x]
>>> x
['A', 'B', 'C', 'D']
ast.literal_eval:
With ast.literal_eval, you can safely evaluate an expression node or a string c...