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How to inherit constructors?
...sider why you have so many constructors and consider reducing them to only one or two in the base class. The derived classes can then mask out some of them using constant values like null and only expose the necessary ones through their constructors.
Update
In C#4 you could specify default parameter...
Why is it not possible to extend annotations in Java?
...Q, where it says:
Why don’t you support annotation subtyping (where one annotation type extends another)?
It complicates the annotation type
system, and makes it much more
difficult to write “Specific Tools”.
…
“Specific Tools” — Programs that query
known anno...
Are there any cases when it's preferable to use a plain old Thread object instead of one of the newe
... when it's necessary or useful to use a plain old Thread object instead of one of the above constructs?
Sure. In precisely those cases where one of the higher-level constructs does not meet your needs.
My advice is that if you find yourself in a situation where existing higher-abstraction tools ...
Ball to Ball Collision - Detection and Handling
... elastic collision between the balls, you only need to worry about the component of the velocity that is in the direction of the collision. The other component (tangent to the collision) will stay the same for both balls. You can get the collision components by creating a unit vector pointing in the...
How can I remove all objects but one from the workspace in R?
I have a workspace with lots of objects and I would like to remove all but one. Ideally I would like to avoid having to type rm(obj.1, obj.2... obj.n) . Is it possible to indicate remove all objects but these ones ?
...
How to check if element has any children in Javascript?
...
A couple of ways:
if (element.firstChild) {
// It has at least one
}
or the hasChildNodes() function:
if (element.hasChildNodes()) {
// It has at least one
}
or the length property of childNodes:
if (element.childNodes.length > 0) { // Or just `if (element.childNodes.length)...
How to make the division of 2 ints produce a float instead of another int?
...
Just cast one of the two operands to a float first.
v = (float)s / t;
The cast has higher precedence than the division, so happens before the division.
The other operand will be effectively automatically cast to a float by the comp...
C++ : why bool is 8 bits long?
... I'm wondering why the bool type is 8 bits long (on my system), where only one bit is enough to hold the boolean value ?
6 ...
Two single-column indexes vs one two-column index in MySQL?
...
If you have two single column indexes, only one of them will be used in your example.
If you have an index with two columns, the query might be faster (you should measure). A two column index can also be used as a single column index, but only for the column listed fi...
What's better to use in PHP, $array[] = $value or array_push($array, $value)?
...enchmarks, but I personally feel like $array[] is cleaner to look at, and honestly splitting hairs over milliseconds is pretty irrelevant unless you plan on appending hundreds of thousands of strings to your array.
Edit: Ran this code:
$t = microtime(true);
$array = array();
for($i = 0; $i < 1000...