UnQL

      rc = 0;
    }
  }
  return rc;
}

/*

** Return TRUE if and only if all of the following are true:
**
**   (1)  pA exists
**   (2)  pB exists and is an array or structure.
**   (3)  pA is value contained within pB
*/
static int withinOperator(JsonNode *pA, JsonNode *pB){
................................................................................
    }
    default: {
      rc = 0;
    }
  }
  return rc;
}











/*
** Evaluate an expression.  Return the result as a JSON object.
**
** The caller must free the returned JSON by a call xjdJsonFree().
*/
JsonNode *xjd1ExprEval(Expr *p){
................................................................................
    }

    /* The x[y] operator. The result depends on the type of value x.
    **
    ** If x is of type XJD1_STRUCT, then expression y is converted to
    ** a string. The value returned is the value of property y of 
    ** object x.







    */
    case TK_LB: {
      pJLeft = xjd1ExprEval(p->u.bi.pLeft);
      pJRight = xjd1ExprEval(p->u.bi.pRight);


      switch( pJLeft->eJType ){
        case XJD1_STRUCT: {
          String idx;
          xjd1StringInit(&idx, 0, 0);
          xjd1JsonToString(pJRight, &idx);
          pRes = getProperty(pJLeft, idx.zBuf);
          xjd1StringClear(&idx);
          break;
        }

        case XJD1_ARRAY:









        case XJD1_STRING: {





















          break;
        }

        default:
          pRes = nullJson();
          break;
      }

      xjd1JsonFree(pJLeft);
      xjd1JsonFree(pJRight);

      return pRes;
    }

    case TK_ID: {
      if( p->pQuery ){
        return xjd1QueryDoc(p->pQuery, p->u.id.zId);
      }else{

      rc = 0;
    }
  }
  return rc;
}

/*
** Evaluate an expression.  Return the result as a JSON object.
** Return TRUE if and only if all of the following are true:
**
**   (1)  pA exists
**   (2)  pB exists and is an array or structure.
**   (3)  pA is value contained within pB
*/
static int withinOperator(JsonNode *pA, JsonNode *pB){
................................................................................
    }
    default: {
      rc = 0;
    }
  }
  return rc;
}

/*
** Assuming zIn points to the first byte of a UTF-8 character,
** advance zIn to point to the first byte of the next UTF-8 character.
*/
#define XJD1_SKIP_UTF8(zIn) {                          \
    if( (*(zIn++))>=0xc0 ){                            \
          while( (*zIn & 0xc0)==0x80 ){ zIn++; }       \
    }                                                  \
}

/*
** Evaluate an expression.  Return the result as a JSON object.
**
** The caller must free the returned JSON by a call xjdJsonFree().
*/
JsonNode *xjd1ExprEval(Expr *p){
................................................................................
    }

    /* The x[y] operator. The result depends on the type of value x.
    **
    ** If x is of type XJD1_STRUCT, then expression y is converted to
    ** a string. The value returned is the value of property y of 
    ** object x.
    **
    ** If x is of type XJD1_ARRAY, then expression y is converted to
    ** a number. If that number is an integer, then it is the index of
    ** the array element to return.
    **
    ** If x is of type XJD1_STRING, then it is treated as an array of 
    ** characters. Processing proceeds as for XJD1_ARRAY.
    */
    case TK_LB: {
      pJLeft = xjd1ExprEval(p->u.bi.pLeft);
      pJRight = xjd1ExprEval(p->u.bi.pRight);
      pRes = 0;

      switch( pJLeft->eJType ){
        case XJD1_STRUCT: {
          String idx;
          xjd1StringInit(&idx, 0, 0);
          xjd1JsonToString(pJRight, &idx);
          pRes = getProperty(pJLeft, idx.zBuf);
          xjd1StringClear(&idx);
          break;
        }

        case XJD1_ARRAY: {
          int iIdx;
          if( xjd1JsonToReal(pJRight, &rRight) ) break;
          iIdx = (int)rRight;
          if( (double)iIdx==rRight && iIdx>=0 && iIdx<pJLeft->u.ar.nElem ){
            pRes = xjd1JsonRef(pJLeft->u.ar.apElem[iIdx]);
          }
          break;
        }

        case XJD1_STRING: {
          int iIdx;
          if( xjd1JsonToReal(pJRight, &rRight) ) break;
          iIdx = (int)rRight;
          if( (double)iIdx==rRight && iIdx>=0 ){
            char *z = pJLeft->u.z;
            for(z=pJLeft->u.z; *z && iIdx!=0; iIdx--){
              XJD1_SKIP_UTF8(z);
            }
            if( *z ){
              String x;
              char *zEnd = z;
              pRes = xjd1JsonNew(0);
              if( pRes ){
                XJD1_SKIP_UTF8(zEnd);
                xjd1StringInit(&x, 0, 0);
                xjd1StringAppend(&x, z, zEnd-z);
                pRes->eJType = XJD1_STRING;
                pRes->u.z = xjd1StringGet(&x);
              }
            }
          }
          break;
        }

        default:

          break;
      }

      xjd1JsonFree(pJLeft);
      xjd1JsonFree(pJRight);
      if( pRes==0 ) pRes = nullJson();
      return pRes;
    }

    case TK_ID: {
      if( p->pQuery ){
        return xjd1QueryDoc(p->pQuery, p->u.id.zId);
      }else{

.testcase 17
CREATE COLLECTION c2;
INSERT INTO c2 VALUE { a:1, b:2, c:"d", d:3 };
SELECT c2.a FROM c2;
SELECT c2["b"] FROM c2;
SELECT c2[c2.c] FROM c2;

.result 1 2 3

.testcase 17
CREATE COLLECTION c2;
INSERT INTO c2 VALUE { a:1, b:2, c:"d", d:3 };
SELECT c2.a FROM c2;
SELECT c2["b"] FROM c2;
SELECT c2[c2.c] FROM c2;
SELECT c2["e"] FROM c2;
.result 1 2 3 null

.testcase 18
DELETE FROM c2;
INSERT INTO c2 VALUE { x: [10,11,12,13,14,15,16] };
SELECT c2.x[0]          FROM c2;
SELECT c2.x["1"]        FROM c2;
SELECT c2.x[2.01]       FROM c2;
SELECT c2.x[c2.x[6]-13] FROM c2;
SELECT c2.x[-1]         FROM c2;
SELECT c2.x[7]          FROM c2;
.result 10 11 null 13 null null

.testcase 19
DELETE FROM c2;
INSERT INTO c2 VALUE { x: "abcdefg" };
SELECT c2.x[0]       FROM c2;
SELECT c2.x["1"]     FROM c2;
SELECT c2.x[2.01]    FROM c2;
SELECT c2.x[1+1+1]   FROM c2;
SELECT c2.x[-1]      FROM c2;
SELECT c2.x[7]       FROM c2;
SELECT c2.x[0][0][0] FROM c2;
.result "a" "b" null "d" null null "a"