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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...
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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How do I link to Google Maps with a particular longitude and latitude?
I have a small application that gives the current location: longitude and latitude.
Now I have to browse to google maps with the longitude and latitude.
Please suggest how I can do this.
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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 ...
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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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 get IntelliJ to recognize common Python modules?
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Just create and add Python SDK
File -> Project Structure -> Project -> Project SDK -> new
and select the installation path of your Python interpreter (for
example, C:\Python26 in windows and /usr/bin/python2.7 in Linux) as...
How to tell Xcode where my info.plist and .pch files are
I renamed my project and it's files and now Xcode is still looking for the old info.plist file. Where do I set the locations of the .plist and .pch files that it needs.
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What is the effect of extern “C” in C++?
...then link to using the C name.
Since C++ has overloading of function names and C does not, the C++ compiler cannot just use the function name as a unique id to link to, so it mangles the name by adding information about the arguments. A C compiler does not need to mangle the name since you can not ...