Difference between export and changing parameters in a function module

[Former Member]

I thought Import parameters take values from outside of a Function Module (FM) and Export parameters returns new values. Recently encountered an example where export parameter is filled with a value before the FM call and the value is passed into the FM. I can access and change the value in the FM.

Is this the standard behaviour of Export parameters? If so what is the difference between Export and Changing parameters?

[retired_member]

Pass the parameter by value and you'll see.

https://help.sap.com/http.svc/rc/abapdocu_751_index_htm/7.51/en-US/index.htm?file=abenformal_paramet...

[Former Member]

Thanks for the response.

I saw the different behaviour when tried it on an RFC yesterday but could not understood why. Come to think of it, since I pass it as a reference it is pretty normal to see the value in FM.