Create a structure type at runtime

Question

Hi friends,
is it possible to create a local structure type dynamically(at run time).My situation is as follows :
The user gives a period of time - for Example from "05.03.2009" to "04.03.2010"
Depending on the number of months between the period of time 
I have to create a structure with field names as follows:
I have calculated the number of months between a period of time and the field name also(Mar-09.Apr-09 extra) using function modules.
The question that is running around my head now is how to create the local structure type at run time with the field names.
TYPES: BEGIN of st_testStruct
     matnr type string,
     land type string,
     "The above to fields in the structure will always be there but depending on the period of time.
     the following fields have to created dynamically.
     Mar-09 type string,     " as the time period starts from "05.03.2009"
     apr-09 type string,
     may-09 type string,
     ........so on
     dec-09 type string,
     jan-10 type string,
     feb-10 type string,
     mar-10 type string,
end of st_testStruct.
depending on the time range the number of field could be more or less in the structure type.Thats why I want to create it dynamically.
Any sample code for this purpose is useful.....
Thanks
P

Answer 1

ABAP RTTS is what you're looking for - check out this [Wiki page|http://wiki.sdn.sap.com/wiki/display/ABAP/RuntimeTypeServices+%28RTTS%29], which should answer your questions... (here's the link to the [ABAP online docu|http://help.sap.com/abapdocu_70/en/ABENRTTI.htm])
Cheers, harald
p.s.: Don't use the hyphen in your field names. This was a bad practice that was used in some old releases. The problem is that fields in a structure are addressed with a hyphen, e.g. like mara-matnr.