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When would you use a WeakHashMap or a WeakReference?
...
One problem with strong references is
caching, particular with very large
structures like images. Suppose you
have an application which has to work
with user-supplied images, like the
web site design tool I work on....
The SQL OVER() clause - when and why is it useful?
...use.
The PARTITION BY clause let's you break up your aggregate functions. One obvious and useful example would be if you wanted to generate line numbers for order lines on an order:
SELECT
O.order_id,
O.order_date,
ROW_NUMBER() OVER(PARTITION BY O.order_id) AS line_item_no,
OL.prod...
Why no ICloneable?
Is there a particular reason why a generic ICloneable<T> does not exist?
9 Answers
...
ExecutorService that interrupts tasks after a timeout
...he cancel is a no op and work continues unchanged. There only needs to be one extra thread scheudling to cancel the tasks and one thread to run them. You could have two executors, one to submit your main tasks and one to cancel them.
– John Vint
May 3 '10 at ...
Why use jQuery on() instead of click()
...ick', function() { // code
});
In the sense that it only add the handler one time to all elements with class elementClass. If you have a new elementClass coming from, for example $('<div class="elementClass" />'), the handler won't be bound on that new element, you need to do:
$('#container...
Why does C++ rand() seem to generate only numbers of the same order of magnitude?
...bout the distribution. Uniform is just a special case, albeit an important one. Might be a good place to point out various distributions from the C++11 standard library.
– leftaroundabout
Jun 20 '13 at 21:43
...
How do you detect the clearing of a “search” HTML5 input?
... "update panel" function was called once, on FF twice for every keystroke (one in keyup, one in change)
Additionally, clearing the field with the small X (which is not present under FF) fired the search event under Chrome: no keyup, no change.
The conclusion? Use input instead:
$(some-input).on(...
How to override !important?
...)
add a CSS rule with the same selector at a later point than the existing one (in a tie, the last one defined wins).
Some examples with a higher specificity (first is highest/overrides, third is lowest):
table td {height: 50px !important;}
.myTable td {height: 50px !important;}
#myTable td {h...
How to create streams from string in Node.Js?
...is itself a iterable, so Readable.from("input string") will work, but emit one event per character. Readable.from(["input string"]) will emit one event per item in the array (in this case, one item).
Also note that in later nodes (probably 12.3, since the documentation says the function was changed...
jQuery vs document.querySelectorAll
...terface.
If you only want the selector engine from jQuery you can use the one jQuery itself is using: Sizzle That way you have the power of jQuerys Selector engine without the nasty overhead.
EDIT:
Just for the record, I'm a huge vanilla JavaScript fan. Nonetheless it's a fact that you sometimes n...