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What is the difference between a var and val definition in Scala?
What is the difference between a var and val definition in Scala and why does the language need both? Why would you choose a val over a var and vice versa?
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Mongodb Explain for Aggregation framework
...t, $geonear at the beginning of a pipeline) as well as subsequent $lookup and $graphLookup stages. Once data has been fetched into the aggregation pipeline for processing (e.g. passing through stages like $project, $unwind, and $group) further manipulation will be in-memory (possibly using temporar...
Swift compiler segmentation fault when building
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When you run into a compiler segfault in Swift, you don't get a handy line number and error message. Here's how you can track the problem down:
Create a new file called SegFaultDebugger.swift in your project.
In this new file, define an extension to the class that's giving you problems.
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Difference between git checkout --track origin/branch and git checkout -b branch origin/branch
Does anybody know the difference between these two commands to switch and track a remote branch?
4 Answers
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What is the difference between NaN and None?
I am reading two columns of a csv file using pandas readcsv() and then assigning the values to a dictionary. The columns contain strings of numbers and letters. Occasionally there are cases where a cell is empty. In my opinion, the value read to that dictionary entry should be None but instead ...
In PHP, what is a closure and why does it use the “use” identifier?
I'm checking out some PHP 5.3.0 features and ran across some code on the site that looks quite funny:
6 Answers
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How do I parse a URL query parameters, in Javascript? [duplicate]
...@cmfolio)
array parameters (@user2368055)
proper use of decodeURIComponent and non-encoded = (@AndrewF)
non-encoded + (added by me)
For further details, see MDN article and RFC 3986.
Maybe this should go to codereview SE, but here is safer and regexp-free code:
function getJsonFromUrl(url) {
i...
Check if a string contains an element from a list (of strings)
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With LINQ, and using C# (I don't know VB much these days):
bool b = listOfStrings.Any(s=>myString.Contains(s));
or (shorter and more efficient, but arguably less clear):
bool b = listOfStrings.Any(myString.Contains);
If you wer...
How do I set the proxy to be used by the JVM
...e Internet. The most common example happens when it is reading an XML file and needs to download its schema.
19 Answers
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How to convert a column number (e.g. 127) into an Excel column (e.g. AA)
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For better understanding, I would replace the 65 with 'A'
– Stef Heyenrath
Nov 11 '11 at 11:12
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