: $f EDPOS @ PREVPOS @ 2DUP = IF 2DROP EXIT THEN
    2DUP > IF DUP pos! SWAP THEN
    ( p1 p2, p1 < p2 ) OVER - ( pos len ) FBUF _zbuf
    SWAP _cpos FBUF ( len src dst ) ROT MOVE ;
: $R ( replace mode )
    mode! 'R' EMIT
    BEGIN setpos C< DUP 0xd = NOT IF
        EDPOS @ _cpos C! 1 EDPOS +! BLK!! 0
    THEN UNTIL mode! SPC contents ;
: handle ( c -- f )
    DUP '0' '9' =><= IF num 0 EXIT THEN
    DUP CMD 2+ C! CMD FIND IF EXECUTE ELSE DROP THEN
    UPPER 'Q' = ;