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When to wrap quotes around a shell variable?
... quote it if it can either be empty or contain spaces (or any whitespace really) or special characters (wildcards). Not quoting strings with spaces often leads to the shell breaking apart a single argument into many.
$? doesn't need quotes since it's a numeric value. Whether $URL needs it depends o...
Is non-blocking I/O really faster than multi-threaded blocking I/O? How?
...ocking or asynchronous I/O is that your thread can continue its work in parallel. Of course you can achieve this also using an additional thread. As you stated for best overall (system) performance I guess it would be better to use asynchronous I/O and not multiple threads (so reducing thread switch...
How to place the ~/.composer/vendor/bin directory in your PATH?
I'm on Ubuntu 14.04 and I've been trying all possible methods to install Laravel to no avail. Error messages everything I try. I'm now trying the first method in the quickstart documentation, that is, via Laravel Installer, but it says to "Make sure to place the ~/.composer/vendor/bin directory in...
Chrome DevTools Devices does not detect device when plugged in
...s://developers.google.com/chrome-developer-tools/docs/remote-debugging
Install Windows USB driver http://developer.samsung.com/android/tools-sdks/Samsung-Android-USB-Driver-for-Windows
Install Android SDK http://developer.android.com/sdk/index.html
Install Android SDK Platform-tools http://developer...
Convert String to Type in C# [duplicate]
...he type (with its namespace, of course) if the type is in mscorlib or the calling assembly. Otherwise, you've got to include the assembly name as well:
Type type = Type.GetType("Namespace.MyClass, MyAssembly");
If the assembly is strongly named, you've got to include all that information too. See...
How to wrap async function calls into a sync function in Node.js or Javascript?
...pose you maintain a library that exposes a function getData . Your users call it to get actual data:
var output = getData();
Under the hood data is saved in a file so you implemented getData using Node.js built-in fs.readFileSync . It's obvious both getData and fs.readFileSync are sync ...
Is there a version control system for database structure changes?
...keeps track of your current db version.
To migrate up, you run a command called "db:migrate" which looks at your version and applies the needed scripts. You can migrate down in a similar way.
The migration scripts themselves are kept in a version control system -- whenever you change the database ...
What is the best CSS Framework and are they worth the effort?
...um I've came across the world of CSS Frameworks. The one I've been specifically looking at is BluePrint . I was wondering if anyone else had come across CSS frameworks, suggest which is the best and if they are worth the effort?
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How can I define colors as variables in CSS?
...les, so that I can just change a variable to have the new color applied to all elements that use it?
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Most efficient way to prepend a value to an array
...g-O performance if you are ok with modifying the array in-place. If you really can't mutate the original array then you would do something like the below snippet, which doesn't seem to be appreciably faster than your solution:
a.slice().unshift(0); // Use "slice" to avoid mutating "a".
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