Commit | Line | Data |
---|---|---|
7836cfa3 JM |
1 | @io.sql |
2 | @types.sql | |
3 | @reader.sql | |
4 | @printer.sql | |
5 | ||
6 | -- --------------------------------------------------------- | |
7 | -- step1_read_print.sql | |
8 | ||
9 | CREATE OR REPLACE PACKAGE mal_pkg IS | |
10 | ||
11 | FUNCTION MAIN(pwd varchar) RETURN integer; | |
12 | ||
13 | END mal_pkg; | |
14 | / | |
15 | ||
16 | CREATE OR REPLACE PACKAGE BODY mal_pkg IS | |
17 | ||
18 | FUNCTION MAIN(pwd varchar) RETURN integer IS | |
19 | TYPE env_type IS TABLE OF mal_type INDEX BY varchar2(100); | |
20 | repl_env env_type; | |
21 | ||
22 | line varchar2(4000); | |
23 | ||
24 | -- read | |
25 | FUNCTION READ(line varchar) RETURN mal_type IS | |
26 | BEGIN | |
27 | RETURN reader_pkg.read_str(line); | |
28 | END; | |
29 | ||
30 | -- eval | |
31 | ||
32 | -- forward declarations | |
33 | FUNCTION EVAL(ast mal_type, env env_type) RETURN mal_type; | |
34 | FUNCTION do_core_func(fn mal_type, args mal_seq_items_type) RETURN mal_type; | |
35 | ||
36 | FUNCTION eval_ast(ast mal_type, env env_type) RETURN mal_type IS | |
37 | i integer; | |
38 | old_seq mal_seq_items_type; | |
39 | new_seq mal_seq_items_type; | |
40 | f mal_type; | |
41 | BEGIN | |
42 | IF ast.type_id = 7 THEN | |
43 | RETURN env(TREAT(ast AS mal_str_type).val_str); | |
44 | ELSIF ast.type_id IN (8,9) THEN | |
45 | old_seq := TREAT(ast AS mal_seq_type).val_seq; | |
46 | new_seq := mal_seq_items_type(); | |
47 | new_seq.EXTEND(old_seq.COUNT); | |
48 | FOR i IN 1..old_seq.COUNT LOOP | |
49 | new_seq(i) := EVAL(old_seq(i), env); | |
50 | END LOOP; | |
51 | RETURN mal_seq_type(ast.type_id, new_seq); | |
52 | ELSE | |
53 | RETURN ast; | |
54 | END IF; | |
55 | END; | |
56 | ||
57 | FUNCTION EVAL(ast mal_type, env env_type) RETURN mal_type IS | |
58 | el mal_type; | |
59 | f mal_type; | |
60 | args mal_seq_type; | |
61 | BEGIN | |
62 | IF ast.type_id <> 8 THEN | |
63 | RETURN eval_ast(ast, env); | |
64 | END IF; | |
65 | ||
66 | -- apply | |
67 | el := eval_ast(ast, env); | |
68 | f := types_pkg.first(el); | |
69 | args := TREAT(types_pkg.slice(el, 1) AS mal_seq_type); | |
70 | RETURN do_core_func(f, args.val_seq); | |
71 | END; | |
72 | ||
73 | ||
74 | FUNCTION PRINT(exp mal_type) RETURN varchar IS | |
75 | BEGIN | |
76 | RETURN printer_pkg.pr_str(exp); | |
77 | END; | |
78 | ||
79 | -- stub to support wrap.sh | |
80 | PROCEDURE env_vset(env integer, name varchar, val varchar) IS | |
81 | BEGIN | |
82 | RETURN; | |
83 | END; | |
84 | ||
85 | -- repl | |
86 | FUNCTION mal_add(args mal_seq_items_type) RETURN mal_type IS | |
87 | BEGIN | |
88 | RETURN mal_int_type(3, TREAT(args(1) AS mal_int_type).val_int + | |
89 | TREAT(args(2) AS mal_int_type).val_int); | |
90 | END; | |
91 | ||
92 | FUNCTION mal_subtract(args mal_seq_items_type) RETURN mal_type IS | |
93 | BEGIN | |
94 | RETURN mal_int_type(3, TREAT(args(1) AS mal_int_type).val_int - | |
95 | TREAT(args(2) AS mal_int_type).val_int); | |
96 | END; | |
97 | ||
98 | FUNCTION mal_multiply(args mal_seq_items_type) RETURN mal_type IS | |
99 | BEGIN | |
100 | RETURN mal_int_type(3, TREAT(args(1) AS mal_int_type).val_int * | |
101 | TREAT(args(2) AS mal_int_type).val_int); | |
102 | END; | |
103 | ||
104 | FUNCTION mal_divide(args mal_seq_items_type) RETURN mal_type IS | |
105 | BEGIN | |
106 | RETURN mal_int_type(3, TREAT(args(1) AS mal_int_type).val_int / | |
107 | TREAT(args(2) AS mal_int_type).val_int); | |
108 | END; | |
109 | ||
110 | FUNCTION do_core_func(fn mal_type, args mal_seq_items_type) RETURN mal_type IS | |
111 | fname varchar(100); | |
112 | BEGIN | |
113 | IF fn.type_id <> 11 THEN | |
114 | raise_application_error(-20004, | |
115 | 'Invalid function call', TRUE); | |
116 | END IF; | |
117 | ||
118 | fname := TREAT(fn AS mal_str_type).val_str; | |
119 | CASE | |
120 | WHEN fname = '+' THEN RETURN mal_add(args); | |
121 | WHEN fname = '-' THEN RETURN mal_subtract(args); | |
122 | WHEN fname = '*' THEN RETURN mal_multiply(args); | |
123 | WHEN fname = '/' THEN RETURN mal_divide(args); | |
124 | ELSE raise_application_error(-20004, | |
125 | 'Invalid function call', TRUE); | |
126 | END CASE; | |
127 | END; | |
128 | ||
129 | FUNCTION REP(line varchar) RETURN varchar IS | |
130 | BEGIN | |
131 | RETURN PRINT(EVAL(READ(line), repl_env)); | |
132 | END; | |
133 | ||
134 | BEGIN | |
135 | repl_env('+') := mal_str_type(11, '+'); | |
136 | repl_env('-') := mal_str_type(11, '-'); | |
137 | repl_env('*') := mal_str_type(11, '*'); | |
138 | repl_env('/') := mal_str_type(11, '/'); | |
139 | ||
140 | WHILE true | |
141 | LOOP | |
142 | BEGIN | |
143 | line := stream_readline('user> ', 0); | |
144 | -- stream_writeline('line: [' || line || ']', 1); | |
145 | IF line IS NULL THEN RETURN 0; END IF; | |
146 | IF line IS NOT NULL THEN | |
147 | stream_writeline(REP(line)); | |
148 | END IF; | |
149 | ||
150 | EXCEPTION WHEN OTHERS THEN | |
151 | IF SQLCODE = -20000 THEN | |
152 | RETURN 0; | |
153 | END IF; | |
154 | stream_writeline('Error: ' || SQLERRM); | |
155 | END; | |
156 | END LOOP; | |
157 | END; | |
158 | ||
159 | END mal_pkg; | |
160 | / | |
161 | show errors; | |
162 | ||
163 | quit; |