Inform the user if a script is incomplete

Created by: huntergoldstein

Problem

The following, if placed in a script, will run without any output and setting the status to 0:

for i in 0..10

If this were run as part of an interactive session Ion would prompt the user for more input.

Solution

Have Shell somehow check the current flow control after executing a script. If the flow control indicates a partial command in memory, indicate the command and exit with a non-zero status.