The
stripPrefix function drops the given prefix
from a list. It returns
Nothing if the list did not start with
the prefix given, or
Just the list after the prefix, if it
does.
Examples
>>> stripPrefix "foo" "foobar"
Just "bar"
>>> stripPrefix "foo" "foo"
Just ""
>>> stripPrefix "foo" "barfoo"
Nothing
>>> stripPrefix "foo" "barfoobaz"
Nothing