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Why does casting int to invalid enum value NOT throw exception?
...ted .NET. An enum is backed by another value type (int, short, byte, etc), and so it can actually have any value that is valid for those value types.
I personally am not a fan of the way this works, so I made a series of utility methods:
/// <summary>
/// Utility methods for enum values. Thi...
Unmangling the result of std::type_info::name
... information about the calling function. This should be relatively easy, standard C++ has a type_info class. This contains the name of the typeid'd class/function/etc. but it's mangled. It's not very useful. I.e. typeid(std::vector<int>).name() returns St6vectorIiSaIiEE .
...
The “backspace” escape character '\b': unexpected behavior?
So I'm finally reading through K&R , and I learned something within the first few pages, that there is a backspace escape character, \b .
...
How long does it take for GitHub page to show changes after changing index.html
...t (or break a cache) you can append a query string like myfile.jpg?ver=123 and every time you update the string the cache will bust, and you can verify that the CDN is updating.
– Joel Glovier
Dec 19 '16 at 14:10
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How can I bind to the change event of a textarea in jQuery?
...tarea> . Like typing any characters (deleting,backspace) or mouse click and paste or cut. Is there a jQuery event that can trigger for all those events?
...
Chrome refuses to execute an AJAX script due to wrong MIME type
I'm trying to access a script as JSON via AJAX, which works fine on Safari and other browsers but unfortunately will not execute in Chrome. It's coming with the following error:
...
How to set response filename without forcing “save as” dialog
... what you meant by 'not widely supported' back when you wrote this answer, and wish you'd given hard facts instead of FUD. I just tested in IE 6, IE 8, modern Chrome, and modern Firefox, and it works in all of them; as far as I can tell, it's totally safe to use this nowadays.
–...
jQuery clone() not cloning event bindings, even with on()
...f custom jQuery events for use in mobile web applications. They work great and have been tested. However, I have run into a small problem which I am having trouble understanding.
...
Selecting only numeric columns from a data frame
...list-apply functions:
nums <- unlist(lapply(x, is.numeric))
Then standard subsetting
x[ , nums]
## don't use sapply, even though it's less code
## nums <- sapply(x, is.numeric)
For a more idiomatic modern R I'd now recommend
x[ , purrr::map_lgl(x, is.numeric)]
Less codey, less ref...
Add new field to every document in a MongoDB collection
...to add a new_field to all your collection, you have to use empty selector, and set multi flag to true (last param) to update all the documents
db.your_collection.update(
{},
{ $set: {"new_field": 1} },
false,
true
)
EDIT:
In the above example last 2 fields false, true specifies the upser...