2.11BSD#431 - /usr/src/new/PORT/B/src/bint/b2tes.c

   1: /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
   2: 
   3: /*
   4:   $Header: b2tes.c,v 1.4 85/08/22 16:57:17 timo Exp $
   5: */
   6: 
   7: #include "b.h"
   8: #include "b1obj.h"
   9: #include "b2par.h"
  10: #include "b2key.h"
  11: #include "b2syn.h"
  12: #include "b2nod.h"
  13: #include "b3err.h"
  14: 
  15: Forward bool conjunction(), disjunction();
  16: Forward parsetree right_test();
  17: 
  18: Visible parsetree test(q) txptr q; {
  19:     parsetree v;
  20:     skipsp(&tx);
  21:     if (!(conjunction(q, &v) || disjunction(q, &v))) v= right_test(q);
  22:     return v;
  23: }
  24: 
  25: Forward bool negation(), quantification();
  26: Forward parsetree tight_test();
  27: 
  28: Hidden parsetree right_test(q) txptr q; {
  29:     parsetree v;
  30:     skipsp(&tx);
  31:     if (!(negation(q, &v) || quantification(q, &v))) v= tight_test(q);
  32:     return v;
  33: }
  34: 
  35: Hidden bool conjunction(q, v) txptr q; parsetree *v; {
  36:     txptr ftx, ttx;
  37:     if (find(K_AND, q, &ftx, &ttx)) {
  38:         parsetree t;
  39:         t= tight_test(ftx); tx= ttx;
  40:         if (!conjunction(q, v)) *v= right_test(q);
  41:         *v= node3(AND, t, *v);
  42:         return Yes;
  43:     }
  44:     return No;
  45: }
  46: 
  47: Hidden bool disjunction(q, v) txptr q; parsetree *v; {
  48:     txptr ftx, ttx;
  49:     if (find(K_OR, q, &ftx, &ttx)) {
  50:         parsetree t;
  51:         t= tight_test(ftx); tx= ttx;
  52:         if (!disjunction(q, v)) *v= right_test(q);
  53:         *v= node3(OR, t, *v);
  54:         return Yes;
  55:     }
  56:     return No;
  57: }
  58: 
  59: Hidden bool negation(q, v) txptr q; parsetree *v; {
  60:     if (not_keyword()) {
  61:         *v= node2(NOT, right_test(q));
  62:         return Yes;
  63:     }
  64:     return No;
  65: }
  66: 
  67: Hidden bool quantification(q, v) txptr q; parsetree *v; {
  68:     bool some, each;
  69:     if ((some= some_keyword()) || (each= each_keyword()) || no_keyword()) {
  70:         parsetree t, e; typenode type;
  71:         txptr utx, vtx, ftx, ttx;
  72:         req(K_HAS, ceol, &utx, &vtx);
  73:         if (utx > q) {
  74:             parerr(MESS(2700, "HAS follows colon"));
  75:             /* as in: SOME i IN x: SHOW i HAS a */
  76:             utx= tx; vtx= q;
  77:         }
  78:         if (find(K_IN_quant, utx, &ftx, &ttx)) {
  79:             idf_cntxt= In_ranger;
  80:             t= idf(ftx); tx= ttx;
  81:             type= some ? SOME_IN : each ? EACH_IN : NO_IN;
  82:         } else if (find(K_PARSING, utx, &ftx, &ttx)) {
  83:             idf_cntxt= In_ranger;
  84:             t= idf(ftx);
  85:             if (nodetype(t) != COLLATERAL)
  86:                 pprerr(MESS(2701, "no collateral_identifier where expected"));
  87:             tx= ttx;
  88:             type= some ? SOME_PARSING : each ? EACH_PARSING
  89:                   : NO_PARSING;
  90:         } else {
  91:             parerr(MESS(2702, "neither IN nor PARSING found"));
  92:             utx= tx; vtx= q; t= NilTree; type= Nonode;
  93:         }
  94:         e= expr(utx); tx= vtx;
  95:         *v= node4(type, t, e, right_test(q));
  96:         return Yes;
  97:     }
  98:     return No;
  99: }
 100: 
 101: Forward bool cl_test(), order_test();
 102: Forward parsetree ref_or_prop();
 103: 
 104: Hidden parsetree tight_test(q) txptr q; {
 105:     parsetree v;
 106:     skipsp(&tx);
 107:     if (nothing(q, "test")) v= NilTree;
 108:     else if (!(cl_test(q, &v) || order_test(q, &v))) {
 109:         if (is_expr(Char(tx))) v= ref_or_prop(q);
 110:         else {
 111:             parerr(MESS(2703, "no test where expected"));
 112:             v= NilTree;
 113:         }
 114:     }
 115:     upto_test(q);
 116:     return v;
 117: }
 118: 
 119: Hidden bool cl_test(q, v) txptr q; parsetree *v; {
 120:     txptr tx0= tx;
 121:     if (open_sign()) { /* (expr) or (test) */
 122:         txptr ftx, ttx, tx1;
 123:         tx1= tx;
 124:         req(")", q, &ftx, &ttx); tx= ttx;
 125:         skipsp(&tx);
 126:         if (!Text(q)) {
 127:             tx= tx1;
 128:             *v= compound(ttx, test);
 129:             return Yes;
 130:         }
 131:     }
 132:     tx= tx0;
 133:     return No;
 134: }
 135: 
 136: Forward typenode relop();
 137: 
 138: Hidden bool order_test(q, v) txptr q; parsetree *v; {
 139:     txptr ftx;
 140:     if (findrel(q, &ftx)) {
 141:         typenode r;
 142:         *v= singexpr(ftx);
 143:         do {
 144:             r= relop();
 145:             if (!findrel(q, &ftx)) ftx= q;
 146:             *v= node3(r, *v, singexpr(ftx));
 147:         } while (ftx < q);
 148:         return Yes;
 149:     }
 150:     return No;
 151: }
 152: 
 153: Hidden typenode relop() {
 154:     skipsp(&tx);
 155:     return
 156:         at_most_sign()      ? AT_MOST :
 157:         unequal_sign()      ? UNEQUAL :
 158:         at_least_sign()     ? AT_LEAST :
 159:         equals_sign()       ? EQUAL :
 160:         less_than_sign()    ? LESS_THAN :
 161:         greater_than_sign() ? GREATER_THAN :
 162:         /* psyserr */         Nonode;
 163: }
 164: 
 165: /* refined_test or proposition */
 166: 
 167: Forward parsetree dyadic_proposition();
 168: 
 169: Hidden parsetree ref_or_prop(q) txptr q; {
 170:     value t1;
 171:     txptr tx0= tx;
 172:     if (tag_operator(q, &t1)) {
 173:         value t2;
 174:         skipsp(&tx);
 175:         if (!Text(q)) return node2(TAG, t1);
 176:         if (tag_operator(q, &t2)) {
 177:             skipsp(&tx);
 178:             if (!Text(q))
 179:                 return node4(MONPRD, t1, node2(TAG, t2), Vnil);
 180:             release(t1); release(t2);
 181:             return (tx= tx0, unp_test(q));
 182:         }
 183:         release(t1);
 184:         if (!dya_sign()) return (tx= tx0, unp_test(q));
 185:     }
 186:     return (tx= tx0, dyadic_proposition(q));
 187: }
 188: 
 189: Visible bool dya_proposition= No;
 190: 
 191: Hidden parsetree dyadic_proposition(q) txptr q; {
 192:     parsetree v; value name;
 193:     dya_proposition= Yes;
 194:     v= singexpr(q);
 195:     if (!Text(q)) /* unparsed */
 196:         return v;
 197:     if (!tag_operator(q, &name)) {
 198:         parerr(MESS(2704, "no dyadic predicate where expected"));
 199:         name= Vnil;
 200:     }
 201:     return node5(DYAPRD, v, name, singexpr(q), Vnil);
 202: }
 203: 
 204: Hidden Procedure upto_test(q) txptr q; {
 205:     skipsp(&tx);
 206:     if (Text(q)) {
 207:         txptr ftx, ttx;
 208:         if (find(K_AND, q, &ftx, &ttx) || find(K_OR, q, &ftx, &ttx)) {
 209:             tx= ftx;
 210:             parerr(MESS(2705, "cannot determine priorities; use ( and ) to resolve"));
 211:         } else parerr(MESS(2706, "something unexpected following test"));
 212:         tx= q;
 213:     }
 214: }

Defined functions

Defined variables