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What does LINQ return when the results are empty
I have a question about LINQ query. Normally a query returns a IEnumerable<T> type. If the return is empty, not sure if it is null or not. I am not sure if the following ToList() will throw an exception or just a empty List<string> if nothing found in IEnumerable result?
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How to exit an if clause
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Ideally you can achieve both, but there are times when you must trade good code for good performance. Those times are rare, especially when you are considering using Python. In other words: don't worry so much about function c...
No identities were available - administrator request
...one)
In your project's build settings update your code signing identities (all of them) to the new one if there is one. (The old one was probably expired which is one of the biggest causes for the error message you saw)
Verify that your bundle ID is correct (CaSe SeNsEtIvE)
Back to XCode Organizer -...
Best way to allow plugins for a PHP application
... 5 = 9
4 * 5 = 20
Notes:
For this example source code, you must declare all your plugins before the actual source code that you want to be extendable. I've included an example of how to handle single or multiple values being passed to the plugin. The hardest part of this is writing the actual d...
How do I install a plugin for vim?
... that it's completely safe (symlinks don't overwrite existing files, uninstall only deletes symlinks) and easy to keep things updated.
# Easily install vim plugins from a source control checkout (e.g. Github)
#
# alias vim-install=rake -f ~/.vim/rakefile-vim-install
# vim-install
# vim-install unin...
AngularJS: Basic example to use authentication in Single Page Application
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I've created a github repo summing up this article basically: https://medium.com/opinionated-angularjs/techniques-for-authentication-in-angularjs-applications-7bbf0346acec
ng-login Github repo
Plunker
I'll try to explain as good as possible, hope I help some of you out there:
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Static constant string (class member)
...files
const string A::RECTANGLE = "rectangle";
The syntax you were originally trying to use (initializer inside class definition) is only allowed with integral and enum types.
Starting from C++17 you have another option, which is quite similar to your original declaration: inline variables
// ...
What do commas and spaces in multiple classes mean in CSS?
..._12 .grid_6,
.container_16 .grid_8 {
width: 460px;
}
That says "make all .grid_6's within .container_12's and all .grid_8's within .container_16's 460 pixels wide." So both of the following will render the same:
<div class="container_12">
<div class="grid_6">460px Wide</div&g...
How to add extension methods to Enums
... methods for existing classes in a way other people on your team might actually discover and use. Given that enums are classes like any other it shouldn’t be too surprising that you can extend them, like:
enum Duration { Day, Week, Month };
static class DurationExtensions
{
public static Date...
Does deleting a branch in git remove it from the history?
...as a complete source tree, it is a very different structure from svn where all branches and tags (by convention) live in separate 'folders' of the repository alongside the special 'trunk'.
If the branch was merged into another branch before it was deleted then all of the commits will still be reach...