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1.1 root 1: /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
2:
3: /*
4: $Header: b2cmd.c,v 1.4 85/08/22 16:54:17 timo Exp $
5: */
6:
7: #include "b.h"
8: #include "b0fea.h"
9: #include "b1obj.h"
10: #include "b2par.h"
11: #include "b2key.h"
12: #include "b2syn.h"
13: #include "b2nod.h"
14: #include "b3env.h"
15: #include "b3err.h"
16: #include "b3ext.h"
17:
18: /* ******************************************************************** */
19: /* command_suite */
20: /* ******************************************************************** */
21:
22: Forward parsetree cmd_seq();
23:
24: Visible parsetree cmd_suite(cil, first) intlet cil; bool first; {
25: if (ateol())
26: return cmd_seq(cil, first);
27: else {
28: parsetree v; value c; intlet l= lino;
29: suite_command(&v, &c);
30: return node5(SUITE, mk_integer(l), v, c, NilTree);
31: }
32: }
33:
34: Hidden parsetree cmd_seq(cil, first) intlet cil; bool first; {
35: value c; intlet level, l;
36: level= ilev(); l= lino;
37: if (is_comment(&c))
38: return node5(SUITE, mk_integer(l), NilTree, c,
39: cmd_seq(cil, first));
40: if ((level == cil && !first) || (level > cil && first)) {
41: parsetree v;
42: findceol();
43: suite_command(&v, &c);
44: return node5(SUITE, mk_integer(l), v, c, cmd_seq(level, No));
45: }
46: veli();
47: return NilTree;
48: }
49:
50: Visible Procedure suite_command(v, c) parsetree *v; value *c; {
51: *v= NilTree; *c= Vnil;
52: if (!(control_command(v) || simple_command(v, c)))
53: parerr(MESS(2000, "no command where expected"));
54: }
55:
56: /* ******************************************************************** */
57: /* is_comment, tail_line */
58: /* ******************************************************************** */
59:
60: Visible bool is_comment(v) value *v; {
61: txptr tx0= tx;
62: skipsp(&tx);
63: if (comment_sign()) {
64: while (Space(Char(tx0-1))) tx0--;
65: while (!Eol(tx)) tx++;
66: *v= cr_text(tx0, tx);
67: return Yes;
68: }
69: tx= tx0;
70: return No;
71: }
72:
73: Visible value tail_line() {
74: value v;
75: if (is_comment(&v)) return v;
76: if (!ateol()) parerr(MESS(2001, "something unexpected following this line"));
77: return Vnil;
78: }
79:
80: /* ******************************************************************** */
81: /* simple_command */
82: /* */
83: /* ******************************************************************** */
84:
85: Forward bool bas_com(), term_com(), udr_com();
86:
87: Visible bool simple_command(v, c) parsetree *v; value *c; {
88: return bas_com(v) || term_com(v) || udr_com(v)
89: ? (*c= tail_line(), Yes) : No;
90: }
91:
92: /* ******************************************************************** */
93: /* basic_command */
94: /* ******************************************************************** */
95:
96: Forward value cr_newlines();
97:
98: Hidden bool bas_com(v) parsetree *v; {
99: txptr ftx, ttx; parsetree e, t;
100: if (check_keyword()) {
101: *v= node2(CHECK, test(ceol));
102: } else if (choose_keyword()) {
103: req(K_FROM_choose, ceol, &ftx, &ttx);
104: t= targ(ftx); tx= ttx;
105: *v= node3(CHOOSE, t, expr(ceol));
106: } else if (delete_keyword()) {
107: *v= node2(DELETE, targ(ceol));
108: } else if (draw_keyword()) {
109: *v= node2(DRAW, targ(ceol));
110: } else if (insert_keyword()) {
111: req(K_IN_insert, ceol, &ftx, &ttx);
112: e= expr(ftx); tx= ttx;
113: *v= node3(INSERT, e, targ(ceol));
114: } else if (put_keyword()) {
115: req(K_IN_put, ceol, &ftx, &ttx);
116: e= expr(ftx); tx= ttx;
117: *v= node3(PUT, e, targ(ceol));
118: } else if (read_keyword()) {
119: if (find(K_RAW, ceol, &ftx, &ttx)) {
120: *v= node2(READ_RAW, targ(ftx)); tx= ttx;
121: upto(ceol, K_RAW);
122: } else {
123: req(K_EG, ceol, &ftx, &ttx);
124: t= targ(ftx); tx= ttx;
125: *v= node3(READ, t, expr(ceol));
126: }
127: } else if (remove_keyword()) {
128: req(K_FROM_remove, ceol, &ftx, &ttx);
129: e= expr(ftx); tx= ttx;
130: *v= node3(REMOVE, e, targ(ceol));
131: } else if (setrandom_keyword()) {
132: *v= node2(SET_RANDOM, expr(ceol));
133: } else if (write_keyword()) {
134: intlet b_cnt= 0, a_cnt= 0;
135: skipsp(&tx);
136: if (Ceol(tx))
137: parerr(MESS(2002, "no parameter where expected"));
138: while (nwl_sign()) {b_cnt++; skipsp(&tx); }
139: if (Ceol(tx)) e= NilTree;
140: else {
141: ftx= ceol;
142: while (Space(Char(ftx-1)) || Char(ftx-1) == '/')
143: if (Char(--ftx) == '/') a_cnt++;
144: skipsp(&tx);
145: e= ftx > tx ? expr(ftx) : NilTree;
146: }
147: *v= node4(WRITE,
148: cr_newlines(b_cnt), e, cr_newlines(a_cnt));
149: tx= ceol;
150: } else return No;
151: return Yes;
152: }
153:
154: Hidden value cr_newlines(cnt) intlet cnt; {
155: value v, t= mk_text("/"), n= mk_integer(cnt);
156: v= repeat(t, n);
157: release(t); release(n);
158: return v;
159: }
160:
161: /* ******************************************************************** */
162: /* terminating_command */
163: /* ******************************************************************** */
164:
165: Visible bool term_com(v) parsetree *v; {
166: if (fail_keyword()) {
167: upto(ceol, K_FAIL);
168: *v= node1(FAIL);
169: } else if (quit_keyword()) {
170: upto(ceol, K_QUIT);
171: *v= node1(QUIT);
172: } else if (return_keyword())
173: *v= node2(RETURN, expr(ceol));
174: else if (report_keyword())
175: *v= node2(REPORT, test(ceol));
176: else if (succeed_keyword()) {
177: upto(ceol, K_SUCCEED);
178: *v= node1(SUCCEED);
179: } else return No;
180: return Yes;
181: }
182:
183: /* ******************************************************************** */
184: /* user_defined_command; refined_command */
185: /* ******************************************************************** */
186:
187: Forward value hu_actuals();
188: #ifdef EXT_COMMAND
189: Forward bool extended_command();
190: #endif
191:
192: Hidden bool udr_com(v) parsetree *v; {
193: value w;
194: if (is_keyword(&w)) {
195: #ifdef EXT_COMMAND
196: if (extended_command(w, v))
197: return Yes;
198: #endif
199: if (!in(w, kwlist)) {
200: *v= node4(USER_COMMAND,
201: copy(w), hu_actuals(ceol, w), Vnil);
202: return Yes;
203: }
204: release(w);
205: }
206: return No;
207: }
208:
209: Hidden value hu_actuals(q, kw) txptr q; value kw; {
210: parsetree e; value v, w;
211: txptr ftx;
212: skipsp(&tx);
213: if (!findkw(q, &ftx)) ftx= q;
214: e= Text(ftx) ? expr(ftx) : NilTree;
215: v= Text(q) ? hu_actuals(q, keyword()) : Vnil;
216: w= node5(ACTUAL, kw, e, v, Vnil);
217: return w;
218: }
219:
220: #ifdef EXT_COMMAND
221:
222: /* ******************************************************************** */
223: /* extended_command */
224: /* ******************************************************************** */
225:
226: Hidden bool extended_command(w, v) value w, *v; {
227: string name, arg; ext *e; int i; value args[MAXEARGS], a;
228: txptr ftx, ttx;
229: extern bool extcmds; /* Flag set in main by -E option */
230: if (!extcmds) return No;
231: name= strval(w);
232: for (e= extensions; e->e_name != 0; ++e) {
233: if (strcmp(e->e_name, name) == 0) break;
234: }
235: if (e->e_name == 0) return No;
236: for (i= 0; i < MAXEARGS && (arg= e->e_args[i]) != 0; ++i) {
237: if (arg[1] != '\0') req(arg+1, ceol, &ftx, &ttx);
238: else ftx= ceol;
239: switch (arg[0]) {
240: case 'e': args[i]= expr(ftx); break;
241: case 't': args[i]= targ(ftx); break;
242: default: psyserr(MESS(2003, "bad entry in extended_command table"));
243: }
244: if (arg[1] != '\0') tx= ttx;
245: }
246: if (i == 0) arg= e->e_name;
247: else {
248: arg= e->e_args[i-1];
249: if (arg[1] != '\0') ++arg;
250: else switch (arg[0]) {
251: case 'e': arg= "expression"; break;
252: case 't': arg= "target"; break;
253: }
254: }
255: upto(ceol, arg);
256: if (i == 0) a= Vnil;
257: else {
258: a= mk_compound(i);
259: while (--i >= 0) *Field(a, i)= args[i];
260: }
261: *v= node3(EXTENDED_COMMAND, w, a);
262: return Yes;
263: }
264:
265: #endif EXT_COMMAND
266:
267: /* ******************************************************************** */
268: /* control_command */
269: /* ******************************************************************** */
270:
271: Forward parsetree alt_suite();
272:
273: Visible bool control_command(v) parsetree *v; {
274: parsetree e, t; value c;
275: txptr ftx, ttx, utx, vtx;
276: skipsp(&tx);
277: if (if_keyword()) {
278: req(":", ceol, &utx, &vtx);
279: t= test(utx); tx= vtx;
280: if (!is_comment(&c)) c= Vnil;
281: *v= node4(IF, t, c, cmd_suite(cur_ilev, Yes));
282: } else if (select_keyword()) {
283: need(":");
284: c= tail_line();
285: *v= node3(SELECT, c, alt_suite());
286: } else if (while_keyword()) {
287: req(":", ceol, &utx, &vtx);
288: t= test(utx); tx= vtx;
289: if (!is_comment(&c)) c= Vnil;
290: *v= node4(WHILE, t, c, cmd_suite(cur_ilev, Yes));
291: } else if (for_keyword()) {
292: req(":", ceol, &utx, &vtx);
293: req(K_IN_for, ceol, &ftx, &ttx);
294: if (ttx > utx) {
295: parerr(MESS(2004, "IN after colon"));
296: ftx= utx= tx; ttx= vtx= ceol;
297: }
298: idf_cntxt= In_ranger;
299: t= idf(ftx); tx= ttx;
300: e= expr(utx); tx= vtx;
301: if (!is_comment(&c)) c= Vnil;
302: *v= node5(FOR, t, e, c, cmd_suite(cur_ilev, Yes));
303: } else return No;
304: return Yes;
305: }
306:
307: /* ******************************************************************** */
308: /* alternative_suite */
309: /* ******************************************************************** */
310:
311: Forward parsetree alt_seq();
312:
313: Hidden parsetree alt_suite() {
314: parsetree v; bool empty= Yes;
315: v= alt_seq(&empty, cur_ilev, Yes, No);
316: if (empty) parerr(MESS(2005, "no alternative suite where expected"));
317: return v;
318: }
319:
320: Hidden parsetree
321: alt_seq(empty, cil, first, else_encountered)
322: bool *empty, first, else_encountered; intlet cil;
323: {
324: value c; intlet level, l;
325: level= ilev(); l= lino;
326: if (is_comment(&c))
327: return node6(TEST_SUITE, mk_integer(l), NilTree, c, NilTree,
328: alt_seq(empty, cil, first, else_encountered));
329: if ((level == cil && !first) || (level > cil && first)) {
330: parsetree v, s; txptr ftx, ttx;
331: if (else_encountered)
332: parerr(MESS(2006, "after ELSE no more alternatives allowed"));
333: findceol();
334: req(":", ceol, &ftx, &ttx);
335: *empty= No;
336: if (else_keyword()) {
337: upto(ftx, K_ELSE); tx= ttx;
338: if (!is_comment(&c)) c= Vnil;
339: s= cmd_suite(level, Yes);
340: release(alt_seq(empty, level, No, Yes));
341: return node4(ELSE, mk_integer(l), c, s);
342: }
343: v= test(ftx); tx= ttx;
344: if (!is_comment(&c)) c= Vnil;
345: s= cmd_suite(level, Yes);
346: return node6(TEST_SUITE, mk_integer(l), v, c, s,
347: alt_seq(empty, level, No, else_encountered));
348: }
349: veli();
350: return NilTree;
351: }
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