dolist iterates over the elements of a list.
The body of dolist is like a tagbody.
It consists of a series of tags and statements.
which should produce a list. It then executes the body
once for each element in the list, in the order in which the
tags and statements occur, with
var bound to the element.
At the time result-form is processed,
var is bound to nil.
An implicit block
named nil surrounds dolist.
return may be used to terminate the loop immediately without
performing any further iterations, returning zero or more values.
The scope of the binding of var
does not include the list-form,
but the result-form is included.
It is implementation-dependent whether dolist
establishes a new binding of var on each iteration
or whether it establishes a binding for var once at the
beginning and then assigns it on any subsequent iterations.