Scala can be used as a scripting language. To demonstrate, create HelloWorld.scala
with the following content:
println("Hello")
Execute it with the command-line interpreter (the $
is the command line prompt):
$ scala HelloWorld.scala
Hello
If you omit .scala
(such as if you simply typed scala HelloWorld
) the runner will look for a compiled .class
file with bytecode instead of compiling and then executing the script.
Note: If scala is used as a scripting language no package can be defined.
In operating systems utilizing bash
or similar shell terminals, Scala scripts can be executed using a 'shell preamble'. Create a file named HelloWorld.sh
and place the following as its content:
#!/bin/sh
exec scala "$0" "$@"
!#
println("Hello")
The parts between #!
and !#
is the 'shell preamble', and is interpreted as a bash script. The rest is Scala.
Once you have saved the above file, you must grant it 'executable' permissions. In the shell you can do this:
$ chmod a+x HelloWorld.sh
(Note that this gives permission to everyone: read about chmod to learn how to set it for more specific sets of users.)
Now you can execute the script like this:
$ ./HelloWorld.sh