def matchOnlyAtCol(n):
 def verifyCol(strg, locn, toks):
  if (col(locn, strg) != n):
   raise ParseException(strg, locn, ('matched token not at column %d' % n))
 return verifyCol

def matchOnlyAtCol ( n ) : def verifyCol ( strg , locn , toks ) : if ( col ( locn , strg ) != n ) : raise ParseException ( strg , locn , ( 'matched token not at column %d' % n ) ) return verifyCol
helper method for defining parse actions that require matching at a specific column in the input text .