How To Fix W8186 - Expression & is not a constant

SAP Error Message - Details

• Message type: E = Error

• Message class: W8 - Workflow: Expressions, data flow

• Message number: 186

• Message text: Expression & is not a constant

What causes this issue?

A constant must be entered in the current function.
In the case of expression &V1&, however, according to SAP Business
Workflow syntax, we are dealing with a variable.

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?

Please enter a constant.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message W8186 - Expression & is not a constant ?

  SAP Error Message:
  
  W8186: Expression & is not a constant
  
  Cause:
  This warning message occurs in ABAP when an expression that is expected to be a constant is not a constant. Typically, this happens in contexts where the ABAP compiler requires a literal or a constant expression, but a variable or a non-constant expression is provided instead.
  For example, this can happen in:
  
  DATA declarations with VALUE or CONSTANTS statements where the value assigned must be a constant.
  SELECT-OPTIONS or PARAMETERS default values that require constants.
  When using expressions in places where only constants are allowed, such as in CONSTANTS declarations or in CASE statements with constant expressions.
  
  
  Explanation:
  In ABAP, a constant is a value that does not change during program execution and is known at compile time. Examples include literals like 'X', 100, or predefined constants declared with the CONSTANTS keyword.
  If you try to assign a variable or an expression that depends on runtime values to a place that requires a constant, the compiler issues this warning.
  
  Example that causes W8186:
  DATA: lv_value TYPE i VALUE 10.
  CONSTANTS: lc_const TYPE i VALUE lv_value. " This causes W8186
  Here, lv_value is a variable, not a constant, so it cannot be used to initialize a constant.
  
  Solution:
  
  Use literal values or constants when defining constants or in places requiring constant expressions.
  If you need to assign a value that is not known at compile time, use a variable (DATA) instead of a constant (CONSTANTS).
  For default values in parameters or select-options, use literals or constants.
  If you want to use an expression, ensure it is composed only of constants and literals.
  
  
  Corrected example:
  CONSTANTS: lc_const TYPE i VALUE 10.
  DATA: lv_value TYPE i VALUE lc_const.
  Or if the value is dynamic:
  DATA: lv_value TYPE i VALUE 10.
  " Use lv_value as a variable, not as a constant
  
  Related Information:
  
  ABAP Keyword Documentation: Check the documentation for CONSTANTS, DATA, and VALUE statements.
  Compiler Restrictions: Some ABAP statements require compile-time constants; understanding these restrictions helps avoid this warning.
  Debugging: Look at the line number and expression mentioned in the warning to identify where a non-constant is used improperly.
  
  
  Summary:
  
  Cause: Using a non-constant expression where a constant is required.
  Solution: Replace the expression with a literal or a declared constant.
  Check: Use constants or literals in declarations and default values that require constants.
  
  
  If you provide the exact code snippet causing the warning, I can help you fix it specifically.