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`levels
...a functional language and does not like to mutate its objects. But it does allow assignment statements, using replacement functions:
levels(x) <- y
is equivalent to
x <- `levels<-`(x, y)
The trick is, this rewriting is done by <-; it is not done by levels<-. levels<- is just ...
Should MySQL have its timezone set to UTC?
...of the servers you work with then you can have everything set to UTC internally and never worry about timezones and DST.
Here are some notes I collected of how to work with timezones as a form of cheatsheet for myself and others which might influence what timezone the person will choose for his/he...
Detecting an undefined object property
...is the special value `undefined`");
}
To check if an object does not actually have such a property, and will therefore return undefined by default when you try and access it:
if(!o.hasOwnProperty('myProperty')) {
alert("myProperty does not exist");
}
To check if the value associated with an i...
git --git-dir not working as expected
...
Thanks this worked! Agreed that this is confusing. Its called Keep It Simple Stupid. You can almost always allow flexibility while at the same time giving defaults that make the most sense VS having a command not work at all.
– Nay
Jan 18 '12...
conditional unique constraint
...
That's only partially true onedaywhen. The database behaves consistently and predictably. The check constraint will execute after the row is added to the table and before the transaction is committed by the dbms and you can count on that. ...
How can I get the current date and time in UTC or GMT in Java?
...TC. It's most accurate to say that Date itself doesn't have a time zone at all - it's just an instant in time, which could be regarded in multiple time zones. But when you create an instance, it doesn't depend on your time zone.
– Jon Skeet
Dec 28 '12 at 12:33
...
How to properly overload the
I am writing a small matrix library in C++ for matrix operations. However my compiler complains, where before it did not. This code was left on a shelf for 6 months and in between I upgraded my computer from debian etch to lenny (g++ (Debian 4.3.2-1.1) 4.3.2
) however I have the same problem on a Ub...
How can I tell if a DOM element is visible in the current viewport?
...ut the browser vendors have also created getBoundingClientRect for specifically the purpose of finding element coordinates... Why wouldn't we use it?
– Prestaul
Jul 6 '15 at 15:25
...
Single script to run in both Windows batch and Linux Bash?
...
Actually, I find that # 2>NUL & ECHO Welcome to %COMSPEC%. manages to hide the error about the # command not being found by cmd. This technique is useful when you need to write a standalone line that will only be executed ...
bool operator ++ and --
... and 2 or more [true]).
So as a short-hand ++ worked, and -- didn't.
++ is allowed on bools for compatibility with this, but its use is deprecated in the standard and it was removed in C++17.
This assumes that I only use x as an boolean, meaning that overflow can't happen until I've done ++ often e...