Indirect expression file foldername - ObjectVision/GeoDMS GitHub Wiki

Configuration examples Indirect expression file/foldername

The following example shows how to configure a direct or indirect expression to make a foldername, that can be used to read e.g. multiple files from a data source like the BAG.

The main difference between the configuration of the item folder_direct_expression versus folder_indirect_expression is that the calculation rule for the folder_indirect_expression is evaluated first to a direct expression, before the actual data is calculated. In the GeoDMS GUI the resulting direct calculation rule is presented, in this case just the string: '20220101'.

The advantage of the indirect expression is that the then or else part of the if function does not have to be evaluated/calculated as it is not a part of the resulting direct expression anymore. This is mainly an advantage if the calculation of this part is time or memory consuming.

container in_direct_expressions
{
   parameter<string> date       := '2022';
   parameter<bool>   isDate2022 := date == '2022';

   parameter<string> folder_direct_expression   :=   isDate2022 ? '20220101' : '20230101';
   parameter<string> folder_indirect_expression := = isDate2022 ? '''20220101''' : '''20230101''';

   unit<uint32> bag_pand_direct_expression
   : StorageName = "= 'D:/SourceData/BAG20/snapshots/' + folder_direct_expression + '/pand.fss'"
   {
      attribute<string> identificatie;
   }
   unit<uint32> bag_pand_indirect_expression
   : StorageName = "= 'D:/SourceData/BAG20/snapshots/' + folder_indirect_expression + '/pand.fss'"
   {
      attribute<string> identificatie;
   }
}