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Python idiom to return first item or None
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answered Dec 13 '08 at 23:31
jfsjfs
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Ruby Arrays: select(), collect(), and map()
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edited Oct 23 '18 at 21:01
SgtPooki
8,87155 gold badges2929 silver badges4040 bronze badges
answered M...
How to return a part of an array in Ruby?
...e out of range.
a = [ "a", "b", "c", "d", "e" ]
a[2] + a[0] + a[1] #=> "cab"
a[6] #=> nil
a[1, 2] #=> [ "b", "c" ]
a[1..3] #=> [ "b", "c", "d" ]
a[4..7] #=> [ "e" ]
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new DateTime() vs default(DateTime)
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206
No, they are identical.
default(), for any value type (DateTime is a value type) will always c...
Build.scala, % and %% symbols meaning
...%%:
val appDependencies = Seq(
"org.scala-tools" % "scala-stm_2.9.1" % "0.3"
)
Assuming the scalaVersion for your build is 2.9.1, the following is identical:
val appDependencies = Seq(
"org.scala-tools" %% "scala-stm" % "0.3"
)
As you can see above, if you use %%, you don't have to sp...
Rails mapping array of hashes onto single hash
...g a method call between each element of it.
For example [1, 2, 3].reduce(0, :+) is like saying 0 + 1 + 2 + 3 and gives 6.
In our case we do something similar, but with the merge function, which merges two hashes.
[{:a => 1}, {:b => 2}, {:c => 3}].reduce({}, :merge)
is {}.merge({:a =&g...
How do I position one image on top of another in HTML?
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10 Answers
10
Active
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Fade/dissolve when changing UIImageView's image
...CATransition *transition = [CATransition animation];
transition.duration = 0.25;
transition.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
transition.type = kCATransitionFade;
transition.delegate = self;
[self.view.layer addAnimation:transition forKey:...
Why does ReSharper tell me “implicitly captured closure”?
...ected override void OnLoad(EventArgs e)
{
base.OnLoad(e);
int i = 0;
Random g = new Random();
this.button1.Click += (sender, args) => this.label1.Text = i++.ToString();
this.button2.Click += (sender, args) => this.label1.Text = (g.Next() + i).ToString();
}
I get an "Impl...
Move an item inside a list?
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answered Jul 3 '10 at 23:15
David ZDavid Z
111k2323 gold badges218218 silver badges256256 bronze badges
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