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How do RVM and rbenv actually work?
...any time you run ruby from the command line, or run a script whose shebang reads #!/usr/bin/env ruby, your operating system will find ~/.rbenv/shims/ruby first and run it instead of any other ruby executable you may have installed.
Each shim is a tiny Bash script that in turn runs rbenv exec. So wi...
What is the significance of 1/1/1753 in SQL Server?
...rical. On a board frequented by heavy left-brainers, this is an enjoyable read. And yes, I did go to a liberal arts college.
– Matt Hamsmith
Jan 25 '11 at 20:57
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Check whether number is even or odd
...first bit is set, then the number must be odd. It's usually faster, and it reads just as well in my opinion. I think the reason others don't prefer it over modulus comes down to a lack of understanding of binary.
– crush
Feb 13 '14 at 21:47
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What is the difference between the HashMap and Map objects in Java?
...hich includes the Map interface).
It will probably make more sense if you read Sun's interface tutorial
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Using -performSelector: vs. just calling the method
...iblings performSelectorInBackground:withObject: and performSelectorOnMainThread:withObject:waitUntilDone: are often more useful. For spawning a background thread, and for calling back results to the main thread from said background thread.
– PeyloW
Sep 30 '09 a...
Node.js and CPU intensive requests
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Well, in an environment where web servers are multi-threaded or multi-process and can handle more than one concurrent request, it is very common to spend a couple of seconds on a single request. People have come to expect that. I'd say that the misunderstanding is that node.js i...
Resolve build errors due to circular dependency amongst classes
...sses call functions of the other, you have to move the definitions out.
Read the FAQ:
How can I create two classes that both know about each other?
What special considerations are needed when forward declarations are used with member objects?
What special considerations are needed when forward ...
Unpacking, extended unpacking and nested extended unpacking
...unpack
*(a,b), c = 1,2,3 # a = 1, b = 2, c = 3
I've already explained above why the first line throws an error. The second line is silly but here's why it works:
(*(a, b), c) = (1, 2, 3)
As previously explained, we work from the ends. 3 is assigned to c, and then the remainin...
What does O(log n) mean exactly?
... phone number. Take some white-out and remove each zero.
O(n · n!): We're ready to load the phonebooks onto the shipping dock. Unfortunately, the robot that was supposed to load the books has gone haywire: it's putting the books onto the truck in a random order! Even worse, it loads all the books o...
When should I use nil and NULL in Objective-C?
... Both seem to be pointers to void *. A different answer here already mentions this, but if you dig into objc.h, you'll find the line #define nill __DARWIN_NULL.
– gkb0986
Oct 25 '13 at 3:12
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