! Script to represent tagging of misspelling
! +MIS is the tag telling we have a misspelling
! ^ is the mark linking to +MIS, and X the context.
! Rule 1 gives an X mark for the misspellings of ä, ö
! Rule 2 is a filter (note the => operator) allowing ^ only after X
! Rule 3 deletes the auxiliary symbols.

define Lex "@n.xfst" ("+MIS":"^") ;

define Rule1 ä (->) a X , ö (->) o X || _ ?* "^" ;
define Rule2 "^" =>  X ?* _ ;
define Rule3 X -> 0 .o. "^" -> 0;

regex Lex .o. Rule1 .o. Rule2 .o. Rule3;