Experiment in Compiler Construction
Phn tch t v ng
Experiment in compiler construction - Scanner design
1
Scanner l g?
Trong m t ch ng trnh d ch, thnh ph n th c hi n ch c n ng phn tch
t v ng g i l scanner.
Experiment in compiler construction - Scanner design
2
Scanner l g?
Experiment in compiler construction - Scanner design
3
Nhi m v c a m t scanner
B qua cc k t v ngh a nh : d u tr ng, tab, k t xu ng dng, ch
thch. Pht hi n cc k t khng h p l Pht hi n token
nh danh (identifier) t kha (keyword) s (number) H ng k t special
symbol ...Experiment in compiler construction - Scanner design
4
Nhi m v c a m t scanner
Chuy n l n l t cc token cho b phn tch c php (parser)
Experiment in compiler construction - Scanner design
5
Cc token c a ngn ng KPL
T kha PROGRAM, CONST, TYPE, VAR, PROCEDURE, FUNCTION, BEGIN,
END, ARRAY, OF, INTEGER, CHAR, CALL, IF, ELSE, WHILE, DO, FOR, TO
Ton t := (assign), + (addition), - (subtraction), *
(multiplication), / (division), = (comparison of equality), !=
(comparison of difference), > (comparison of greaterness), <
(comparison of lessness), >= (comparison of greaterness or
equality), ,
