I'd use a function. More flexible, essentially possible to do anything
you can do in a shell script. Though exiting is not generally
recommended:
$ function foo () { cd /usr/share/doc; pwd; }
$ foo
/usr/share/doc
$ pwd
/usr/share/doc
The function works on the current process. No birthing of children
involved (and less blood on your hands afterward).
Of course, there is a cost -- you're burdening your process with
remembering the function (it's stored in the processes environment).
$ typeset -f foo
foo ()
{
cd /usr/share/doc;
pwd
}
To free yourself:
$ unset foo
Peace.