! Tags to be appended to an fst to get spell-relax tags:
define spellrelax [
 â (->) a "aaX" ,
 ê (->) e "aaX" ,
 î (->) i "aaX" ,
 ô (->) o "aaX" ,
 a (->) â "aaX" ,
 i (->) î "aaX" ,
 o (->) ô "aaX" || _ ?* "^a2aa" ];

define Restr1 "^a2aa" => "aaX" ?* _ ;

define Clean "aaX" -> 0,
           "^a2aa" -> 0;

read regex spellrelax .o.
           Restr1     .o.
           Clean ;