variable parameters - not user defined

dear all

I created a data set as expression with
key: xxxx
exp: ( IFTRUE ( PART ( STYP OF SPRE  , 2 , '-' ) EQ '1500' , 1500 , 6000 ) )

inside a geometry ,i set value as RPRO XXXX
The result is nothing done in design.

Is it possible to use a variable parametrics as a design parameter but where the value is read from styp for exemple,and not set by user

This case comes if i want different SPCO with the same catref (and i dont want manipulation from user)

Thank you

dear all

I created a data set as expression with
key: xxxx
exp: ( IFTRUE ( PART ( STYP OF SPRE  , 2 , '-' ) EQ '1500' , 1500 , 6000 ) )

inside a geometry ,i set value as RPRO XXXX
The result is nothing done in design.

Is it possible to use a variable parametrics as a design parameter but where the value is read from styp for exemple,and not set by user

This case comes if i want different SPCO with the same catref (and i dont want manipulation from user)

Thank you