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remove None value from a list without removing the 0 value
...mbda x: x is not None, L) -- You could get rid of the lambda using partial and operator.is_not I think, but it's probably not worth it since the list-comp is so much cleaner.
– mgilson
Apr 19 '13 at 3:36
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How to implement a rule engine?
...ppet compiles the Rules into fast executable code (using Expression trees) and does not need any complicated switch statements:
(Edit : full working example with generic method)
public Func<User, bool> CompileRule(Rule r)
{
var paramUser = Expression.Parameter(typeof(User));
Expression...
How many characters can UTF-8 encode?
... bytes to encode. This covers the remainder of almost all Latin alphabets, and also Greek, Cyrillic, Coptic, Armenian, Hebrew, Arabic, Syriac and Tāna alphabets, as well as Combining Diacritical Marks.
Three bytes are needed for characters in the rest of the Basic Multilingual Plane, which con...
Is Ruby pass by reference or by value?
...has a reference to. (Even this isn't bulletproof, though — both of the standard cloning methods do a shallow copy, so the instance variables of the clone still point to the same objects that the originals did. If the objects referenced by the ivars mutate, that will still show up in the copy, sinc...
Ruby optional parameters
...his method: e.g. If you're trying to make the default value for scope true and you pass in false, scope ||= true won't work. It evaluates the same as nil and will set it to true
– Joshua Pinter
Nov 10 '11 at 5:32
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How do I properly compare strings in C?
...trying to get a program to let a user enter a word or character, store it, and then print it until the user types it again, exiting the program. My code looks like this:
...
CSS /JS to prevent dragging of ghost image?
...ing under the assumption that the ghost image is visual indicator for drag-and-drop (which it is), and that most people who want to hide the ghost image generally don't care if drag-and-drop is disabled altogether.
– BoltClock♦
Jun 26 '14 at 1:28
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Git: fatal: Pathspec is in submodule
...
Removing the directory from git and adding it again worked for me:
git rm --cached directory
git add directory
This works if you purposefully removed the .git directory because you wanted to add directory to your main git project. In my specific case, ...
Interface Builder: What are the UIView's Layout iOS 6/7 Deltas for?
...OS7.
In iOS7, some views can hide the status bar or have it transparent and, in effect, it is overlaid on top of your view. So if you put a UI element at (0.0, 0.0) on iOS6, it will appear below the status bar, but on iOS7 it would appear partially covered underneath the status bar. So in that ...
UICollectionView reloadData not functioning properly in iOS 7
...I'm not sure if I can explain more. After searching, researching, testing and probing. I feel this is an iOS 7 bug. Forcing the main thread will run all UIKit related messages. I seem to run into this when popping to the view from another view controller. I refresh the data on viewWillAppear. I ...