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Best way to check for “empty or null value”
...red May 20 '14 at 18:47
Erwin BrandstetterErwin Brandstetter
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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...
Why shouldn't all functions be async by default?
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First off, thank you for your kind words. It is indeed an awesome feature and I am glad to have been a small part of it.
If all my code is slowly turning async, why not just make it all async by default?
Well, you're exaggerating; all your code isn't turning async. When you add two "plain" in...
What is a bank conflict? (Doing Cuda/OpenCL programming)
I have been reading the programming guide for CUDA and OpenCL, and I cannot figure out what a bank conflict is. They just sort of dive into how to solve the problem without elaborating on the subject itself. Can anybody help me understand it? I have no preference if the help is in the context of CUD...
Difference between variable declaration syntaxes in Javascript (including global variables)?
...gh in practical terms they're not usually big ones.
There's a fourth way, and as of ES2015 (ES6) there's two more. I've added the fourth way at the end, but inserted the ES2015 ways after #1 (you'll see why), so we have:
var a = 0; // 1
let a = 0; // 1.1 (new with ES2015)
const a = 0; //...
Difference between
What is the difference between List<? super T> and List<? extends T> ?
14 Answers
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Several ports (8005, 8080, 8009) required by Tomcat Server at localhost are already in use
... You can confirm this by going to http://localhost:8080 in your webbrowser and check if you get the Tomcat default home page or a Tomcat-specific 404 error page. Both are equally valid evidence that Tomcat runs fine; if it didn't, then you would have gotten a browser specific HTTP connection timeout...
HTML5 best practices; section/header/aside/article elements
There is enough information about HTML5 on the web (and also on stackoverflow), but now I'm curious about the "best practices". Tags like section/headers/article are new, and everyone has different opinions about when/where you should use these tags. So what do you guys think of the following layout...
Environment variables for java installation
...A_TOOL_OPTIONS with value -Dfile.encoding="UTF-8". This ensures that Java (and tools such as Maven) will run with a Charset.defaultCharset() of UTF-8 (instead of the default Windows-1252). This has saved a lot of headaches when wirking with my own code and that of others, which unfortunately often a...
SVN best-practices - working in a team
I'm starting out with SVN. I know the basic commands and understand the base principles. I was wondering if anyone has any tips or best practices for working with Subversion in a team environment.
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