How to use the previously generated provisioning policy attribute in another attribute

Hello,
I have an Active Directory source, it has a create account provisioning policy and that has an attribute samAccountName which is calculated using a complex logic and i have another attribute that needs substring of the samAccountName, is there a way to utilize the previously generated attribute(samAccountName) to feed another attribute in the provisioning policy?

Thanks,
Naveen

If it is sAMAccountName you can use this way. I do have a rule on sAMAccountName and i use this to get the value and append the remaining string for UPN

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