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What’s the difference between “Array()” and “[]” while declaring a JavaScript array?
...mance increase when using new Array() because you can prevent the overflow from happening.
As pointed out in this answer, new Array(5) will not actually add five undefined items to the array. It simply adds space for five items. Be aware that using Array this way makes it difficult to rely on array...
How should I write tests for Forms in Django?
...form and not the view where the form is rendered. Example to get an idea:
from django.test import TestCase
from myapp.forms import MyForm
class MyTests(TestCase):
def test_forms(self):
form_data = {'something': 'something'}
form = MyForm(data=form_data)
self.assertTrue(...
What really is a deque in STL?
...that it was a double linked list, which would allow insertion and deletion from both ends in constant time, but I am troubled by the promise made by the operator [] to be done in constant time. In a linked list, arbitrary access should be O(n), right?
...
MVC Razor view nested foreach's model
...he expression tree would have a node in it that says: "Get 'Some Property' from a 'model'"
This expression tree can be compiled into a function that can be invoked, but as long as it's an expression tree, it's just a collection of nodes.
So what is that good for?
So Func<> or Action<>...
What's the best way to model recurring events in a calendar application?
... this with this solution)
Solution 2 - store instances
Store everything from 1, but also all the instances, linked back to the original appointment.
Problems:
Takes a lot of space (but space is cheap, so minor)
Exceptions must be handled gracefully, especially if you go back and edit the ori...
What does “@private” mean in Objective-C?
...vate means that the ivar (instance variable) can only be accessed directly from within an instance of that same class. However, that may not mean much to you, so let me give you an example. We'll use the init methods of the classes as examples, for simplicity's sake. I'll comment inline to point ...
Convert decimal to binary in python [duplicate]
...
You can also use a function from the numpy module
from numpy import binary_repr
which can also handle leading zeros:
Definition: binary_repr(num, width=None)
Docstring:
Return the binary representation of the input number as a string.
T...
How do you delete an ActiveRecord object?
... 'value') will allow you to delete records
without a primary key
Note: from @hammady's comment, user.destroy won't work if User model has no primary key.
Note 2: From @pavel-chuchuva's comment, destroy_all with conditions and delete_all with conditions has been deprecated in Rails 5.1 - see gui...
What is the difference between “Include Directories” and “Additional Include Directories”
...UDE PATHS
VC++ Directories: Include Directories
this value is inherited from the INCLUDE Windows environment variable which is defined outside of Visual Studio
environment variables can be: global to the computer or have user level scope
The INCLUDE and LIB environment variables are created whe...
When increasing the size of VARCHAR column on a large table could there be any problems?
I'm using SQL Server 2008 and I need to make a VARCHAR field bigger, from (200 to 1200) on a table with about 500k rows. What I need to know is if there are any issues I have not considered.
...