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Determining whether jQuery has not found any element
...t').length is what you're looking for. (If it finds nothing, this will === 0.) So your conditional statement should probably be:
if($('#id').length) { /* code if found */ } else { /* code if not found */ }
You're getting an object returned from that alert because jQuery (almost) always returns the...
Multiple INSERT statements vs. single INSERT with multiple VALUES
I'm running a performance comparison between using 1000 INSERT statements:
4 Answers
4...
How to unstash only certain files?
...e git checkout or git show to restore a specific file.
git checkout stash@{0} -- <filename>
With Git 2.23+ (August 2019), use git restore, which replaces the confusing git checkout command:
git restore -s stash@{0} -- <filename>
That does overwrite filename: make sure you didn't have l...
Append column to pandas dataframe
...t; dat2 = pd.DataFrame({'dat2': [7,6]})
> dat1.join(dat2)
dat1 dat2
0 9 7
1 5 6
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How to see top processes sorted by actual memory usage?
...dsarnold
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What is AssemblyInfo.cs used for?
...tab of the file properties you will see no name,
no description, version 0.0.0.0, etc.
The value associated with assembly:Guid is the ID that will identify
the assembly if it will be exposed as a COM object. So, if your
assembly isn't COM-exposed, you don't need this. It is randomly
gen...
How to make an array of arrays in Java
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answered Jan 24 '11 at 10:54
Jon SkeetJon Skeet
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What does |= (ior) do in Python?
...
Here we apply merge (|) and update (|=) to dicts:
>>> d1 = {"a": 0, "b": 1, "c": 2}
>>> d2 = {"c": 20, "d": 30}
>>> # Merge, |
>>> d1 | d2
{"a": 0, "b": 1, "c": 20, "d": 30}
>>> d1
{"a": 0, "b": 1, "c": 2}
>>> # Update, |=
>>> d1 |=...
Is there a Java equivalent to C#'s 'yield' keyword?
...options I know of is Aviad Ben Dov's infomancers-collections library from 2007 and Jim Blackler's YieldAdapter library from 2008 (which is also mentioned in the other answer).
Both will allow you to write code with yield return-like construct in Java, so both will satisfy your request. The notable ...
How to test multiple variables against a value?
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+500
You misunderstand how boolean expressions work; they don't work like an English sentence and guess that you are talking about the sam...