How to create an empty Scala Map

If you need to create an empty Map in Scala, the following examples show how to create empty immutable and mutable maps.

An empty immutable Map

You can use these approaches to create an empty immutable Scala Map:

val a = Map[Int, String]()
val a = Map.empty[Int, String]

Here’s what they look like in the REPL:

Emptying the Mac OS X trash from the command line

When using a Mac OS X computer, it's easy to forget that it's just Unix running under the hood ... until your iMac graphics card dies and all you can do is use single-user mode, which has no GUI ... then you're reminded very quickly that it's all just Unix.

Take emptying the trash, for instance. Graphically, you right-click the Trash Can icon, then select the Empty menu option. From the Mac command line (Terminal) you just do this:

rm -rf ~/.Trash/*

It's funny how simple that is from the command line.

Git: How do I add an empty directory to a Git project/repository?

Git empty directories FAQ: How do I add an empty directory to a Git repository?

Short answer - you can't. (See below for the workaround.) The design of the Git staging area only accounts for files, as described in the Git FAQ, and other books like Pro Git.

Git empty directories FAQ

Here's the text from the Git FAQ section, "Can I add empty directories to a Git repository":