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Can a pointer to base point to an array of derived objects?
...
When indexing a pointer, the compiler will add the appropriate amount based on the size of what's located inside the array. So say that sizeof(Shape) = 4 (as it has no member variables). But sizeof(Rectangle) = 12 (exact numbers are likely wrong).
So when you index starting at say... 0x0 for t...
Mocking python function based on input arguments
... mock. This allows you to vary the return
value of the call dynamically, based on the input:
>>> def side_effect(value):
... return value + 1
...
>>> m = MagicMock(side_effect=side_effect)
>>> m(1)
2
>>> m(2)
3
>>> m.mock_calls
[call(1), call(2)]
...
What is the need of JSF, when UI can be achieved with JavaScript libraries such as jQuery and Angula
...o plain JS: do more with less code. To take PrimeFaces (jQuery + jQuery UI based) as an example, browse through its showcase to see complete code examples. BootsFaces (jQuery + Bootstrap UI based) has also a showcase with complete code examples. If you study those examples closely, then you'll see t...
How should equals and hashcode be implemented when using JPA and Hibernate
...uring object (or, at least, session) lifetime.
If the above is impossible, base equals() / hashCode() on primary key IF it's set and object identity / System.identityHashCode() otherwise. The important part here is that you need to reload your Set after new entity has been added to it and persisted;...
Sorting list based on values from another list?
...air: pair[0])]
Explained:
zip the two lists.
create a new, sorted list based on the zip using sorted().
using a list comprehension extract the first elements of each pair from the sorted, zipped list.
For more information on how to set\use the key parameter as well as the sorted function in ge...
Fluid or fixed grid system, in responsive design, based on Twitter Bootstrap
...t,
fixed responsive layout.
These fiddles are completely Bootstrap-free, based on pure CSS media queries, which makes them a good starting point, for anyone willing to craft similar solution without using Twitter Bootstrap.
...
Why does the month argument range from 0 to 11 in JavaScript's Date constructor?
...Date, moving them over to java.util.Calendar, but even that still had zero-based months. Developers fed-up with this created the Joda-Time library, which ultimately led to java.time package that's baked in to Java 8 (2014).
In short, it took 18 years for Java to get a correctly designed date/time ...
Virtual member call in a constructor
...s is that the initializers run in order from the most derived class to the base class, and then constructors run in order from the base class to the most derived class (see Eric Lippert's blog for details as to why this is).
Also in .NET objects do not change type as they are constructed, but start...
How do I automatically sort a has_many relationship in Rails?
...ction with an option on has_many itself:
class Article < ActiveRecord::Base
has_many :comments, :order => 'created_at DESC'
end
class Comment < ActiveRecord::Base
belongs_to :article
end
Or, if you want a simple, non-database method of sorting, use sort_by:
article.comments.sort...
Hidden features of HTML
...
My favourite bit is the base tag, which is a life saver if you want to use routing or URL rewriting...
Let's say you are located at:
www.anypage.com/folder/subfolder/
The following is code and results for links from this page.
Regular Anchor:
...