大约有 46,000 项符合查询结果(耗时:0.1038秒) [XML]
How to check if an element is in an array
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Swift 2, 3, 4, 5:
let elements = [1, 2, 3, 4, 5]
if elements.contains(5) {
print("yes")
}
contains() is a protocol extension method of SequenceType (for sequences of Equatable elements) and not a global method as in
earlier releas...
Dictionaries and default values
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Solomon Ucko
2,42022 gold badges1212 silver badges2727 bronze badges
answered Feb 20 '12 at 9:44
MattHMattH
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How to check if a float value is a whole number
...nt n
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27
8
1
0
which means that anything over 3 cubed, (including 10648) was missed out due to the aforementioned imprecision:
>>> (4**3) ** (1.0/3)
3.9999999999999996
>>> 10648 ** (1.0/3)
21.999999999999996
You'd have to check for numbers close to the whole number instead...
What is the “double tilde” (~~) operator in JavaScript? [duplicate]
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4 Answers
4
Active
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What is the difference between print and puts?
...already.
print does not add a new line.
For example:
puts [[1,2,3], [4,5,nil]] Would return:
1
2
3
4
5
Whereas print [[1,2,3], [4,5,nil]]
would return:
[[1,2,3], [4,5,nil]]
Notice how puts does not output the nil value whereas print does.
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How to express a NOT IN query with ActiveRecord/Rails?
...e this since it seems a lot of people come to this, if you are using Rails 4 look at the answers by Trung Lê` and VinniVidiVicci.
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Is there a performance difference between a for loop and a for-each loop?
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From Item 46 in Effective Java by Joshua Bloch :
The for-each loop, introduced in
release 1.5, gets rid of the clutter
and the opportunity for error by
hiding the iterator or index variable
completely. The resulting idiom
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Switch on ranges of integers in JavaScript [duplicate]
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edited Aug 22 '18 at 10:43
Luca Davanzo
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an...
Laravel - Eloquent or Fluent random row
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624
Laravel >= 5.2:
User::inRandomOrder()->get();
or to get the specific number of records
//...
How exactly does tail recursion work?
...lexey Frunze
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2
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