How To Fix FL340 - Identical import/export parameters can refer only to reference field

SAP Error Message - Details

• Message type: E = Error

• Message class: FL - Function Builder messages

• Message number: 340

• Message text: Identical import/export parameters can refer only to reference field

What causes this issue?

You assigned a reference structure to import/export parameters of the
same name in your function module. Only reference fields are allowed
here.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Assign one reference field (without hyphen) to import/export parameters
of the same name.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message FL340 - Identical import/export parameters can refer only to reference field ?

  The SAP error message FL340, which states "Identical import/export parameters can refer only to reference field," typically occurs in the context of ABAP programming, particularly when dealing with function modules or methods that have import and export parameters.
  Cause:
  This error arises when you have defined multiple import or export parameters in a function module or method that have the same name. In ABAP, when you declare parameters with identical names, the system expects them to refer to a single reference field. If they are not defined as reference fields, the system cannot determine which parameter to use, leading to this error.
  Solution:
  To resolve this error, you can take the following steps:
  
  
  Rename Parameters: Ensure that all import and export parameters have unique names. This is the most straightforward solution. For example, if you have two parameters named PARAM, rename them to PARAM1 and PARAM2.
  
  
  Use Reference Fields: If you need to keep the same name for logical reasons, consider using reference fields. This means you can define one parameter as a reference to another, allowing you to maintain the same name while avoiding the error.
  
  
  Check Function Module/Method Definition: Review the definition of the function module or method to ensure that there are no duplicate parameter names. This includes checking for parameters in the importing, exporting, and changing sections.
  
  
  Review Calling Programs: If the function module or method is being called from other programs, ensure that the calling programs are also updated to reflect any changes made to parameter names.
  
  
  Related Information:
  
  ABAP Documentation: Refer to the official SAP ABAP documentation for guidelines on defining function modules and methods, including best practices for naming parameters.
  SAP Community: The SAP Community forums can be a valuable resource for finding similar issues and solutions shared by other developers.
  Debugging: If you are unsure where the error is originating, use the ABAP debugger to step through the code and identify the exact location of the error.
  
  By following these steps, you should be able to resolve the FL340 error and ensure that your function modules or methods are correctly defined.