The modeling tool supports multiple built-in scripting languages you can use for expression specification. Additionally, you can add other scripting languages you may need. However, if your project contains expressions that use a scripting language that is neither built-in nor manually added to the tool, it is considered missing in the tool; thus, the specified expressions cannot be executed, causing errors in the project.

Expression evaluation failure

For example, if you open a table containing a custom column that has an expression with a JavaScript Nashorn script, an 'Expression evaluation failure' error notification is displayed. Since, in this case, JavaScript Nashorn is neither built-in nor added manually to the modeling tool, the script cannot be executed, causing an evaluation error, as shown below. 

 

The error notification indicates the element containing the failed expression. Clicking the icon on the bottom right opens a Notification Window that displays the element name with the script that cannot be executed. 

Expression evaluation failure notification in the Notification Window

The missing language is also indicated in the Expression dialog's Language field for scripts.

Missing language indication in the Expression dialog

Resolving expression evaluation failure

To resolve an expression evaluation failure, do one of the following