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Is there a “null coalescing” operator in JavaScript?
...d otherwise returns its left-hand-side operand.
Please check compatibility before using it.
The JavaScript equivalent of the C# null coalescing operator (??) is using a logical OR (||):
var whatIWant = someString || "Cookies!";
There are cases (clarified below) that the behaviour won't match...
undefined reference to `WinMain@16'
When I try to build a program using Eclipse CDT , I get the following:
6 Answers
6
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What is the purpose of the single underscore “_” variable in Python?
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_ has 5 main conventional uses in Python:
To hold the result of the last executed expression(/statement) in an interactive
interpreter session. This precedent was set by the standard CPython
interpreter, and other interpreters have followed suit
As a general ...
Squash the first two commits in Git? [duplicate]
With git rebase --interactive <commit> you can squash any number of commits together into a single one.
9 Answers
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Get contentEditable caret index position
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The following code assumes:
There is always a single text node within the editable <div> and no other nodes
The editable div does not have the CSS white-space property set to pre
If you need a more general approach that will work content with nested elements...
How does Haskell printf work?
Haskell's type safety is second to none only to dependently-typed languages. But there is some deep magic going on with Text.Printf that seems rather type-wonky.
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How to avoid warning when introducing NAs by coercion
I generally prefer to code R so that I don't get warnings, but I don't know how to avoid getting a warning when using as.numeric to convert a character vector.
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Convert unix time to readable date in pandas dataframe
... 2 columns):
date 358 non-null values
price 358 non-null values
dtypes: float64(1), int64(1)
In [23]: df.head()
Out[23]:
date price
0 1349720105 12.08
1 1349806505 12.35
2 1349892905 12.15
3 1349979305 12.19
4 1350065705 12.15
In [25]: df['date'] = pd.to_datetime(df['d...
Getting the name of a variable as a string
This thread discusses how to get the name of a function as a string in Python:
How to get a function name as a string?
23 ...
How to check if object (variable) is defined in R?
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You want exists():
R> exists("somethingUnknown")
[1] FALSE
R> somethingUnknown <- 42
R> exists("somethingUnknown")
[1] TRUE
R>
shar...