16. Mandatory value operation

Mandatory value operation makes nexl throw error if the current value in operations chain equals to undefined value.
For example:
If someData variable is not defined or not provided ( i.e. it equals to undefined value ), nexl will throw a "mandatory value" error.

Additionally you can provide your custom error message in the following way:
${someData*Please provide an appropriate arg}
nexl will throw a "Please provide an appropriate arg" error message if someData equals undefined value.

You can also provide an error message dynamically as nexl expression followind by the * character:

Watch a demo