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Preferred way to create a Scala list
...do so with a tail-recursive function, foldLeft, or something else is not really relevant.
If you get the elements in the same order you use them, then a ListBuffer is most likely a preferable choice, if performance is critical.
But, if you are not on a critical path and the input is low enough, yo...
Difference between __str__ and __repr__?
...e come right out and say it — I do not believe in debuggers. I don’t really know how to use any debugger, and have never used one seriously. Furthermore, I believe that the big fault in debuggers is their basic nature — most failures I debug happened a long long time ago, in a galaxy far far a...
Make a borderless form movable?
...
This article on CodeProject details a technique. Is basically boils down to:
public const int WM_NCLBUTTONDOWN = 0xA1;
public const int HT_CAPTION = 0x2;
[System.Runtime.InteropServices.DllImport("user32.dll")]
public static extern int SendMessage(IntPtr hWnd, int Msg, int wParam...
HTML5 Email Validation
...e="Submit">
</form>
And when the user press submit, it automatically shows an error message like:
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Test if lists share any items in python
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Short answer: use not set(a).isdisjoint(b), it's generally the fastest.
There are four common ways to test if two lists a and b share any items. The first option is to convert both to sets and check their intersection, as such:
bool(set(a) & set(b))
Because sets are stor...
Why does SSL handshake give 'Could not generate DH keypair' exception?
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This works for me too, but I have added a provider dynamically. Reffer my answer here for details.
– v.ladynev
Nov 22 '15 at 9:19
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Flask-SQLalchemy update a row's information
...e many objects to be updated.
If you want to give add_user permission to all the admins,
rows_changed = User.query.filter_by(role='admin').update(dict(permission='add_user'))
db.session.commit()
Notice that filter_by takes keyword arguments (use only one =) as opposed to filter which takes an e...
What are “first class” objects?
...as
any other object.
A first class object is an entity that can be dynamically created, destroyed, passed to a function, returned as a value, and have all the rights as other variables in the programming language have.
Depending on the language, this can
imply:
being expressible as ...
Python extending with - using super() Python 3 vs Python 2
Originally I wanted to ask this question , but then I found it was already thought of before...
5 Answers
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Is there any Rails function to check if a partial exists?
..., I'm using the following in my Rails 3/3.1 projects:
lookup_context.find_all('posts/_form').any?
The advantage over other solutions I've seen is that this will look in all view paths instead of just your rails root. This is important to me as I have a lot of rails engines.
This also works in R...