syntax error but its from HP Prime Exercises..what up with that?

[tom234]

EXPORT AA()
BEGIN
LOCAL A,L;
L:=[]; (this line has a error inside the box is this syntax out of date?)
REPEAT
REPEAT
A:=GETKEY;
UNTIL A!=-1;
L:=CONCAT(L,A);
UNTIL ISKEYDOWN(48);
RETURN L;
END;



Symbolic computation
and
Mathematics
with
the calculator HP Prime
Renée De Graeve
Lecturer at Grenoble on page 497

Is this texts words out of date with software programing lauguage in use now?