Fossil

static int exprEval(Th_Interp *interp, Expr *pExpr){
  int rc = TH_OK;

  if( pExpr->pOp==0 ){
    /* A literal */
    rc = thSubstWord(interp, pExpr->zValue, pExpr->nValue);
  }else{
    int eArgType = 0;           /* Actual type of arguments */

    /* Argument values */
    int iLeft;
    int iRight;
    double fLeft;
    double fRight;

        if( rc==TH_OK && zRight ){
          rc = Th_ToInt(interp, zRight, nRight, &iRight);
        }
      }  
    }

    if( rc==TH_OK && eArgType==ARG_INTEGER ){
      int iRes = 0;
      switch( pExpr->pOp->eOp ) {
        case OP_MULTIPLY:     iRes = iLeft*iRight;  break;
        case OP_DIVIDE:       iRes = iLeft/iRight;  break;
        case OP_MODULUS:      iRes = iLeft%iRight;  break;
        case OP_ADD:          iRes = iLeft+iRight;  break;
        case OP_SUBTRACT:     iRes = iLeft-iRight;  break;
        case OP_LEFTSHIFT:    iRes = iLeft<<iRight; break;