We are trying to concatenate two arrays, tried the concat, append to list w\\MNI

the second rule you defined is not clear, can you please elaborate that part?

can you please elaborate the rule!Rule1 part? 

the Rule1 you are talking about has two inputs, element1 and element 2,

i have provided you the link, can you please check that?

https://bpmdemo.appcino.com:9999/suite/design/lUB7821xURit2IUeyXdTsJid8JzYqe6dUIgEfR3ADncN3jh58T4hKh3En85QveBKpTBs2h-ipEIAXqSXJCmarYWhikr6Q_bWICa2gIOhOh0-FvprxNJ

This is an 8 year old thread.  If you have current use case that you can't quite figure out, it would likely be far easier to start a new post at this point, as almost all of the coding workarounds mentioned here originally are now no longer necessary due to steadily-progressing technology and new functions.

what will be the type of element1 and element 2? because while executing the rule2, there is a need to pass arguments in the Rule1, so what values must be passed, i am getting an error when i passed two arguments, both are of number type, the error is "the first parameter of apply must be a function and rule" even if i am passing the correct arguments in the Rule1 i.e. numbers, i am not getting the desired output

Hi kumaru, you will want to create a new post with your specific use case.  As this thread is 8 years old, some of the recommendations such as apply() have been superseded, and some of the practitioners here may not even have active accounts on the community any longer.