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Using bitwise OR 0 to floor a number
...ator casts the
number to an integer, thus removing the fractional part
All bitwise operations except unsigned right shift, >>>, work on signed 32-bit integers. So using bitwise operations will convert a float to an integer.
Does it have any advantages over doing Math.floor? Maybe it...
JRuby on Rails vs. Ruby on Rails, what's difference?
...hem from within Ruby code with JRuby. In the other direction you can also call JRuby code from within Java. JRuby can also use the JVM and application server capabilities.
JRuby is usually hosted within Java application servers such as Sun's GlassFish or even the Tomcat web server.
Although you cann...
Paperclip::Errors::MissingRequiredValidatorError with Rails 4
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Starting with Paperclip version 4.0, all attachments are required to include a content_type validation, a file_name validation, or to explicitly state that they're not going to have either.
Paperclip raises Paperclip::Errors::MissingRequiredValidatorError erro...
Placement of the ng-app directive (html vs body)
...nce where you put ng-app.
If you put it on <body> then you have a smaller scope for AngularJS which is slightly faster.
But I have used ng-app on the <html> for manipulating the <title>.
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Linux bash: Multiple variable assignment
... writing the answer bash supporting this syntax was less common (as in installed by default), though I'm not 100% sure.
– Michael Krelin - hacker
Oct 21 '15 at 19:30
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Default visibility for C# classes and members (fields, methods, etc.)?
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All of the information you are looking for can be found here and here (thanks Reed Copsey):
From the first link:
Classes and structs that are declared directly within a namespace (in other words, that are not nested with...
Why do x86-64 instructions on 32-bit registers zero the upper part of the full 64-bit register?
...he CPU would have to wait on. The register renaming mechanism would essentially be defeated if it wasn't done that way.
This way you can write fast code using 32-bit values in 64-bit mode without having to explicitly break dependencies all the time. Without this behaviour, every single 32-bit instr...
Best practices for reducing Garbage Collector activity in Javascript
I have a fairly complex Javascript app, which has a main loop that is called 60 times per second. There seems to be a lot of garbage collection going on (based on the 'sawtooth' output from the Memory timeline in the Chrome dev tools) - and this often impacts the performance of the application.
...
What are the differences between segment trees, interval trees, binary indexed trees and range trees
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All these data structures are used for solving different problems:
Segment tree stores intervals, and optimized for "which of these intervals contains a given point" queries.
Interval tree stores intervals as well, but opti...
Java regex capturing groups indexes
...ithout capturing property, hence named non-capturing group.
A group is usually used when you need to repeat a sequence of patterns, e.g. (\.\w+)+, or to specify where alternation should take effect, e.g. ^(0*1|1*0)$ (^, then 0*1 or 1*0, then $) versus ^0*1|1*0$ (^0*1 or 1*0$).
A capturing group, a...