Nested expressions

nexl expressions can be nested in other nexl expressions. The depth is unlimited.

Let's consider an example:
fieldName = 'age';

person = {
    name: 'John',
    age: 30
};

// resolving a [fieldName] field from person object
personAge = '${person.${fieldName}}';
Here we are resolving the person.age, where age provided as ${fieldName} nested nexl expression.

You can override the fieldName variable value externally via arguments and the result will be calculated dynamically according to the value you provided in HTTP request.