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Help with C# generics error - “The type 'T' must be a non-nullable value type”
I'm new to C# and don't understand why the following code doesn't work.
4 Answers
4
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Sending a message to nil in Objective-C
...x:i]; This will also return 0, but since objectAtIndex: returns a pointer, and a pointer to 0 is nil/NULL, NSLog will be passed nil each time through the loop. (Although NSLog is a function and not a method, it prints out (null) if passed a nil NSString.
In some cases it's nicer to have a NullPoint...
How can I get query string values in JavaScript?
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Update: Sep-2018
You can use URLSearchParams which is simple and has decent (but not complete) browser support.
const urlParams = new URLSearchParams(window.location.search);
const myParam = urlParams.get('myParam');
PS
Unfortunately URLSearchParams don't properly parse query strings ...
How to beautify JSON in Python?
Can someone suggest how I can beautify JSON in Python or through the command line?
13 Answers
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In .NET, which loop runs faster, 'for' or 'foreach'?
...hrough a list with foreach than it does to loop through an array with for, and you're calling that insignificant? That kind of a performance difference might matter for your application, and it might not, but I wouldn't just dismiss it out of hand.
– Robert Harvey
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Git: How to update/checkout a single file from remote origin master?
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Super handy, this worked great. I needed to get a composer.json file and run an update before I updated the rest of the site in production. If I had manually put the composer.json/lock files in place, when I did a pull, it would c...
Mongod complains that there is no /data/db folder
..., e.g. sudo mkdir -p /data/db
Or you need to do su - to become superuser, and then create the directory with mkdir -p /data/db
Note:
MongoDB also has an option where you can create the data directory in another location, but that's generally not a good idea, because it just slightly complicate...
Storyboard - refer to ViewController in AppDelegate
...e storyboard, add the class files for this ViewController into the project and specify the name of the new class in the IB identity inspector. Now how am I going to refer to this ViewController programmatically from the AppDelegate? I've made a variable with the relevant class and turned it into an ...
Download a specific tag with Git
...hole repository.
After the clone, you can list the tags with $ git tag -l and then checkout a specific tag:
$ git checkout tags/<tag_name>
Even better, checkout and create a branch (otherwise you will be on a branch named after the revision number of tag):
$ git checkout tags/<tag_name...
Using querySelectorAll to retrieve direct children
...gt; .foo");
Note that in some cases you can also skip .querySelectorAll and use other good old-fashioned DOM API features. For example, instead of myDiv.querySelectorAll(":scope > *") you could just write myDiv.children, for example.
Otherwise if you can't yet rely on :scope, I can't think of...