Groups assigned for a task are displaying as [Group:102] rather than Group name

Well before making a decision about which approach is better, I would like to suggest to test the approach specified by you. AFAIK, the above approach might not work because the rule which I have attached supports an object that has multiple users or groups in it where as the approach suggested to you deals with an object that has only one user or one group.

For instance let's say a task has been assigned to Group A, Group B, User 1, User 2. So for a single task, you have multiple assignees. And let's assume you have queried the data and applied the above rules for formatting:

getFormattedUserOrGroupName returns you a string which is equivalent to <Name of Group A>; <Name of Group B>; <firstName and lastName of User 1>; <firstName and lastName of User 2>

The approach suggested to you deals with a single value, so your output could end up like <Name of Group A>. In order to overcome this and get a perfect result you need to use a apply function over the approach suggested to you. If you do so, this becomes a heavy rule compared to the rule getFormattedUserOrGroupName as per my knowledge. Because here you are deciding the object's type based on type checking and you need to implement this type check for each and every object in the array. But getFormattedUserOrGroupName does in two steps by using togroup and touser functions on the input.

Please do let me know if you have any questions.

Well before making a decision about which approach is better, I would like to suggest to test the approach specified by you. AFAIK, the above approach might not work because the rule which I have attached supports an object that has multiple users or groups in it where as the approach suggested to you deals with an object that has only one user or one group.

For instance let's say a task has been assigned to Group A, Group B, User 1, User 2. So for a single task, you have multiple assignees. And let's assume you have queried the data and applied the above rules for formatting:

getFormattedUserOrGroupName returns you a string which is equivalent to <Name of Group A>; <Name of Group B>; <firstName and lastName of User 1>; <firstName and lastName of User 2>

The approach suggested to you deals with a single value, so your output could end up like <Name of Group A>. In order to overcome this and get a perfect result you need to use a apply function over the approach suggested to you. If you do so, this becomes a heavy rule compared to the rule getFormattedUserOrGroupName as per my knowledge. Because here you are deciding the object's type based on type checking and you need to implement this type check for each and every object in the array. But getFormattedUserOrGroupName does in two steps by using togroup and touser functions on the input.

Please do let me know if you have any questions.