How To Fix WL304 - Multiple branching using element '&'; value: '&' (WHEN expression '&')

SAP Error Message - Details

• Message type: E = Error

• Message class: WL - Workflow: run-time messages

• Message number: 304

• Message text: Multiple branching using element '&'; value: '&' (WHEN expression '&')

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message WL304 - Multiple branching using element '&'; value: '&' (WHEN expression '&') ?

  The SAP error message WL304 indicates that there is an issue with a multiple branching statement in your ABAP code, specifically when using the WHEN expression in a CASE statement. This error typically arises when the same value is used multiple times in the WHEN clauses of a CASE statement, which is not allowed.
  Cause:
  The error occurs because the CASE statement is designed to evaluate a single expression and branch based on its value. If the same value appears in multiple WHEN clauses, it creates ambiguity about which branch should be executed, leading to the WL304 error.
  Example of the Error:
  DATA: lv_value TYPE i.
  
  lv_value = 1.
  
  CASE lv_value.
    WHEN 1.
      " Do something for case 1
    WHEN 1. " This will cause the WL304 error
      " Do something else for case 1
    WHEN 2.
      " Do something for case 2
  ENDCASE.
  Solution:
  To resolve the WL304 error, you need to ensure that each value in the WHEN clauses is unique. You can either remove the duplicate WHEN clause or combine the logic if necessary.
  Corrected Example:
  DATA: lv_value TYPE i.
  
  lv_value = 1.
  
  CASE lv_value.
    WHEN 1.
      " Do something for case 1
    WHEN 2.
      " Do something for case 2
  ENDCASE.
  Related Information:
  
  ABAP Documentation: Refer to the official SAP ABAP documentation for more details on the CASE statement and its usage.
  Debugging: If you encounter this error, use the ABAP debugger to step through your code and identify the CASE statement causing the issue.
  Code Review: Regularly review your code for potential duplicate values in CASE statements to prevent this error from occurring in the future.
  
  By ensuring that each WHEN clause in your CASE statement is unique, you can avoid the WL304 error and ensure your code executes as intended.