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Can a CSS class inherit one or more other classes?
I feel dumb for having been a web programmer for so long and not knowing the answer to this question, I actually hope it's possible and I just didn't know about rather than what I think is the answer (which is that it's not possible).
...
What exactly are unmanaged resources?
...g Dispose on that object, or (in C#) using the using statement which will handle calling Dispose for you.
If you neglect to Dispose of your unmanaged resources correctly, the garbage collector will eventually handle it for you when the object containing that resource is garbage collected (this is "...
To ARC or not to ARC? What are the pros and cons? [closed]
...ge collection. It has no GC runtime overhead. The compiler inserts retains and releases in all the places you should have anyway. But it's smarter than you and can optimize out the ones that aren't actually needed (just like it can unroll loops, eliminate temporary variables, inline functions, etc.)...
How to create a MySQL hierarchical recursive query
... (select @pv := '19') initialisation
where find_in_set(parent_id, @pv)
and length(@pv := concat(@pv, ',', id))
Here is a fiddle.
Here, the value specified in @pv := '19' should be set to the id of the parent you want to select all the descendants of.
This will work also if a parent has m...
Sort objects in ArrayList by date?
...MyObject o) {
return getDateTime().compareTo(o.getDateTime());
}
}
And then you sort it by calling:
Collections.sort(myList);
However sometimes you don't want to change your model, like when you want to sort on several different properties. In that case, you can create comparator on the f...
Quickly reading very large tables as dataframes
...ahead of time, the table does not contain any column headers or row names, and does not have any pathological characters that I have to worry about.
...
Conversion failed when converting date and/or time from character string while inserting datetime
...e many formats supported by SQL Server - see the MSDN Books Online on CAST and CONVERT. Most of those formats are dependent on what settings you have - therefore, these settings might work some times - and sometimes not.
The way to solve this is to use the (slightly adapted) ISO-8601 date format th...
Fixed point vs Floating point number
I just can't understand fixed point and floating point numbers due to hard to read definitions about them all over Google. But none that I have read provide a simple enough explanation of what they really are. Can I get a plain definition with example?
...
How to securely save username/password (local)?
...hich you need to log into first.
The account details consist of username and password, and they need to be saved locally.
It's just a matter of security, so other people using the same computer can't see everyone's personal data.
What is the best/most secure way to save this data?
...
Specifically, what's dangerous about casting the result of malloc?
... therefore converting the void* pointer actually returned by malloc to int and then to your pointer type due to the explicit cast. On some platforms, int and pointers may take up different numbers of bytes, so the type conversions may lead to data corruption.
Fortunately, modern compilers give warn...