6G. multiple return values
--------------------------
In E you can return any number of return values (max 3 in
Amiga E because of implementation reasons). How?

RETURN <exp>,<exp>,<exp>                 (or ENDPROC, of course)

example:

PROC sincos(rad)
  DEF sin,cos
  /* whatever computation is needed */
ENDPROC sin,cos

call with:

s,c:=sincos(3.14)
s:=sincos(1.00)

as you can see, there's a new statement of the form:

<var> , ... := <exp>

where <exp> makes mostly only sense as function call.
note two things:
- you can decide yourself how many values you wish to receive.
  this makes sense when the first retval is the main one,
  and the second/third optional infos, which might only be
  important to some callers.
- this form is a _statement_. this means that when you would
  call sincos() as part of another expression, only the
  first (the regular) return value is used:   fun(sincos(1.0))