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What's the best name for a non-mutating “add” method on an immutable collection?
...
Unless I'm missing it, System.Linq.Enumerable (and Linq in general) only uses Concat() for "sequence + sequence", never "item + sequence". The problem that someone "might expect it to add two lists together rather than adding a single value to the other list" was explici...
What does “=>” mean in PHP?
...the context of that foreach loop, it assigns the key of the array to $user and the value to $pass.
Example:
$user_list = array(
'dave' => 'apassword',
'steve' => 'secr3t'
);
foreach ($user_list as $user => $pass) {
echo "{$user}'s pass is: {$pass}\n";
}
// Prints:
// "dave's...
Memoization in Haskell?
...f :: Int -> Int
faster_f n = f_list !! n
That performs passably well, and replaces what was going to take O(n^3) time with something that memoizes the intermediate results.
But it still takes linear time just to index to find the memoized answer for mf. This means that results like:
*Main Dat...
How do I correctly clean up a Python object?
__del__(self) above fails with an AttributeError exception. I understand Python doesn't guarantee the existence of "global variables" (member data in this context?) when __del__() is invoked. If that is the case and this is the reason for the exception, how do I make sure the object destructs...
What is the cleanest way to get the progress of JQuery ajax request?
...ng a request, processing the request in the backend to generate some data, and return it back. How can the client side possibly know what is being done in the backend and how much time it will take that it can calculate the progress?
– SexyBeast
Apr 30 '17 at 2...
What can I use instead of the arrow operator, `->`?
... them inconsistently. Becomes really annoying when you work with templates and don't know the precise type.
– Konrad Rudolph
Oct 21 '08 at 10:15
1
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How to implement has_many :through relationships with Mongoid and mongodb?
...ther side. For example:
class Physician
include Mongoid::Document
has_and_belongs_to_many :patients
end
class Patient
include Mongoid::Document
has_and_belongs_to_many :physicians
end
In other words you would eliminate the join table and it would have a similar effect to has_many :throug...
Adding a column to a data.frame
...xt, [[.data.frame.
Data frames can be indexed in several modes. When [ and [[ are used with a single vector index (x[i] or x[[i]]), they index the data frame as if it were a list.
my.dataframe["new.col"] <- a.vector
my.dataframe[["new.col"]] <- a.vector
The data.frame method for $, ...
Google Maps v3 - limit viewable area and zoom level
...a certain area? I want to allow displaying only some area (e.g. a country) and disallow the user to slide elsewhere. Also I want to restrict the zoom level - e.g. only between levels 6 and 9. And I want to use all the base map types.
...
jQuery Popup Bubble/Tooltip [closed]
...ng to make a "bubble" that can popup when the onmouseover event is fired and will stay open as long as the mouse is over the item that threw the onmouseover event OR if the mouse is moved into the bubble. My bubble will need to have all manners of HTML and styling including hyperlinks, images, e...