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Are braces necessary in one-line statements in JavaScript?
I once heard that leaving the curly braces in one-line statements could be harmful in JavaScript. I don't remember the reasoning anymore and a Google search did not help much.
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Regex lookahead, lookbehind and atomic groups
I found these things in my regex body but I haven't got a clue what I can use them for.
Does somebody have examples so I can try to understand how they work?
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App Inventor 2 数学代码块 · App Inventor 2 中文网
... 最小值 (min)
最大值 (max)
平方根 (square root)
绝对值 (abs)
相反数 (neg)
对数 (log)
e^
四舍五入 (round)
上取整 (ceiling)
下取整 (floor)
求模 (modulo)
余数 (remainder)
商 (quotient)
正弦 (sin)
余弦 (cos)
正切 (tan)
反正弦 (asin...
Drop unused factor levels in a subsetted data frame
I have a data frame containing a factor . When I create a subset of this dataframe using subset or another indexing function, a new data frame is created. However, the factor variable retains all of its original levels, even when/if they do not exist in the new dataframe.
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Why is there no logical xor in JavaScript?
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JavaScript traces its ancestry back to C, and C does not have a logical XOR operator. Mainly because it's not useful. Bitwise XOR is extremely useful, but in all my years of programming I have never needed a logical XOR.
If you have two boolean variables ...
Tools for creating Class Diagrams [closed]
Please suggest tools for creating Class Diagrams with the following criteria:
13 Answers
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How to check whether a string contains a substring in JavaScript?
Usually I would expect a String.contains() method, but there doesn't seem to be one.
3 Answers
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What's the difference between `=` and `
I'm using R 2.8.1 and it is possible to use both = and <- as variable assignment operators. What's the difference between them? Which one should I use?
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Locate Git installation folder on Mac OS X
I'm just curious, Where Git get installed (via DMG) on Mac OS X file system?
11 Answers
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Escape curly brace '{' in String.Format [duplicate]
How do I display a literal curly brace character when using the String.Format method?
1 Answer
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