We have functions like apply(fn!functionName, array), reduce(fn!product, accumu

I think this will be useful if I want to create my own version of reduce()

Technically speaking you can build your own custom function that executes any expression if you use the ProcessDesignService API and its evaluateexpression() method forum.appian.com/.../ProcessDesignService.html

Thank you for the link. I agree that it is doable by creating a custom function plugin. However, I just wish that a process designer would have the flexibility of doing so just by using the expression editor.

While creating a expression rule, we can define certain input parameters for that rule. The inputs can be only of certain predefined datatypes.(like Number, boolean, Text, Any etc.) In those predefined datatypes for input params we do not have something like "Function/rule reference".

Suppose the rule I want to create is like - map(rule!mappingFunction, ri!arrint_array ) which maps an array to another array using the passed function.

I do not currently have the means to create such a rule using Expression editor since there is no way to include a function reference as an input parameter.

It would be great to have this functionality for process designers. It certainly is not a must have feature.