## Boolean operations

        prefix    NOT (p: BOOLEAN)   : BOOLEAN
         infix    AND (p,q: BOOLEAN) : BOOLEAN
         infix     OR (p,q: BOOLEAN) : BOOLEAN

`NOT p` is the complement of `p`.

`p AND q` is `TRUE` if both `p` and `q` are `TRUE`. If `p` is `FALSE`, `q` is not evaluated.

`p OR q` is `TRUE` if at least one of `p` and `q` is `TRUE`. If `p` is `TRUE`, `q` is not evaluated.

    Last modified on Wed Apr  3 09:39:11 PST 1996 by heydon
         modified on Mon Apr 18 14:01:10 PDT 1994 by kalsow