>>> lst = list(range(165)) >>> lst[0::10] [0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160] Note that this is around 100 times faster than looping and checking a modulus for each element: $ python -m timeit -s “lst = list(range(1000))” “lst1 = [x for x in lst … Read more
brew help will show you the list of commands that are available. brew list will show you the list of installed packages. You can also append formulae, for example brew list postgres will tell you of files installed by postgres (providing it is indeed installed). brew search <search term> will list the possible packages that … Read more
The only difference on a bytecode level is that the .extend way involves a function call, which is slightly more expensive in Python than the INPLACE_ADD. It’s really nothing you should be worrying about, unless you’re performing this operation billions of times. It is likely, however, that the bottleneck would lie some place else.
In Java terms, Scala’s Seq would be Java’s List, and Scala’s List would be Java’s LinkedList. Note that Seq is a trait, which is equivalent to Java’s interface, but with the equivalent of up-and-coming defender methods. Scala’s List is an abstract class that is extended by Nil and ::, which are the concrete implementations of … Read more
Legacy. List was originally defined to be functional-languages-looking: 1 :: 2 :: Nil // a list list1 ::: list2 // concatenation of two lists list match { case head :: tail => “non-empty” case Nil => “empty” } Of course, Scala evolved other collections, in an ad-hoc manner. When 2.8 came out, the collections were … Read more
Type :colorscheme then Space followed by TAB. or as Peter said, :colorscheme then Space followed by CTRLd The short version of the command is :colo so you can use it in the two previous commands, instead of using the “long form”. If you want to find and preview more themes, there are various websites like … Read more