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Curious null-coalescing operator custom implicit conversion behaviour
...ression Trees it turns (x ?? y) ?? z into nested lambdas, which ensures in-order evaluation without double evaluation. This is obviously not the approach taken by the C# 4.0 compiler. From what I can tell, section 6.1.4 is approached in a very strict manner in this particular code path and the tempo...
Pick a random element from an array
... Int? Also, why doesn't Swift offer an Int alternative to this function or allow a user to specify what type of integer they would like returned?
– Austin A
Sep 27 '14 at 21:10
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Test if lists share any items in python
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Short answer: use not set(a).isdisjoint(b), it's generally the fastest.
There are four common ways to test if two lists a and b share any items. The first option is to convert both to sets and check their intersection, as such:
bool(set(a) & set(b))
Because sets are stor...
How to use classes from .jar files?
...ram in a jar file, and include all the required jars within that. Then, in order to execute your jar, like,
java -jar my_program.jar
you should have a META-INF/MANIFEST.MF file in your jar. See here, for how-to.
share
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How to install PyQt4 on Windows using pip?
...ld than just a pure python code package, which means it can be hard to install it from source.
Make sure you grab the correct Windows wheel file (python version, 32/64 bit), and then use pip to install it - e.g:
C:\path\where\wheel\is\> pip install PyQt4-4.11.4-cp35-none-win_amd64.whl
Should ...
Cartesian product of multiple arrays in JavaScript
...S
Original 2017 Answer: 2-line answer with vanilla JS:
(see updates below)
All of the answers here are overly complicated, most of them take 20 lines of code or even more.
This example uses just two lines of vanilla JavaScript, no lodash, underscore or other libraries:
let f = (a, b) => [].concat...
Is there any Rails function to check if a partial exists?
..., I'm using the following in my Rails 3/3.1 projects:
lookup_context.find_all('posts/_form').any?
The advantage over other solutions I've seen is that this will look in all view paths instead of just your rails root. This is important to me as I have a lot of rails engines.
This also works in R...
Unresolved reference issue in PyCharm
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Manually adding it as you have done is indeed one way of doing this, but there is a simpler method, and that is by simply telling pycharm that you want to add the src folder as a source root, and then adding the sources root to y...
os.path.dirname(__file__) returns empty
... imageUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454...
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo
...fix the problem
Once the jar was added to the build path, I had change the order on the Java Build Path > Order and Export tab - I set the JAR to the first item in the list (it was the last after the /src and /gen items).
I then rebuilt and redeployed the app to my device - it worked as expected ...