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MongoDB atomic “findOrCreate”: findOne, insert if nonexistent, but do not update
as the title says, I want to perform a find (one) for a document, by _id, and if doesn't exist, have it created, then whether it was found or was created, have it returned in the callback.
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How to parse JSON in Scala using standard Scala classes?
... {
"languages": [{
"name": "English",
"is_active": true,
"completeness": 2.5
}, {
"name": "Latin",
"is_active": false,
"completeness": 0.9
}]
}
""".stripMargin
val result = for {
Some(M(m...
What is the meaning of the /dist directory in open source projects?
Since I first saw a dist/ directory in many open source projects, usually on GitHub, I've been wondering what it means.
4...
Angular JS break ForEach
...r for it does not break the forEach loop. It is merly a way to not execute all logic inside the loop.
– Nebulosar
Apr 8 at 13:42
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Convert unix time to readable date in pandas dataframe
...12.15
3 1349979305 12.19
4 1350065705 12.15
In [25]: df['date'] = pd.to_datetime(df['date'],unit='s')
In [26]: df.head()
Out[26]:
date price
0 2012-10-08 18:15:05 12.08
1 2012-10-09 18:15:05 12.35
2 2012-10-10 18:15:05 12.15
3 2012-10-11 18:15:05 12.19
4 2012-10-12 18:15:...
List of Big-O for PHP functions
After using PHP for a while now, I've noticed that not all built-in PHP functions are as fast as expected. Consider these two possible implementations of a function that finds if a number is prime using a cached array of primes.
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Unable to locate tools.jar
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Add JAVA_HOME and the /bin directory to your path. You realize that this answer is two years old, right?
– duffymo
Jul 23 '13 at 12:52
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How to stop unwanted UIButton animation on title change?
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This works for custom buttons:
[UIView setAnimationsEnabled:NO];
[_button setTitle:@"title" forState:UIControlStateNormal];
[UIView setAnimationsEnabled:YES];
For system buttons you need to add this before re-enabling animations (thank you @Klaas):
[_button layoutIfNeeded];
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How do you mock out the file system in C# for unit testing?
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Edit: Install the NuGet package System.IO.Abstractions.
This package did not exist when this answer was originally accepted. The original answer is provided for historical context below:
You could do it by creating an interface:
inter...
Performance surprise with “as” and nullable types
...lable types, and I'm adding a section about using the "as" operator, which allows you to write:
10 Answers
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