Update value of a local variable to new values inside a foreach loop

Question

a!localVariables( local!principalAmount:ri!loanAmount, local!totalMonths: ri!tenure * 12, local!interestForOneMonth: round(ri!interest / 12, 2), local!interest: ( local!interestForOneMonth * local!remainingAmount, ) / 100, local!remainingAmount:local!principalAmount-local!interest, a!forEach( items: enumerate(local!totalMonths) + 1, expression: { local!interest, local!principalAmount, local!remainingAmount, 
 a!save(l ocal!remainingAmount,local!principalAmount-local!interest, ), a!save(local!principalAmount, local!remainingAmount), } ), ) 
 For each iteration of the for loop i want to update the value of local!principalAmount and local!remainingAmount as shown above. Kindly let me know how we do this in Appian.

Harshit Bumb (Appyzie) · Answer

You cannot change the values of a variable in a rule once assigned. Also, a!save() only works on human interactions/events and hence it won't work.
You can just create a new dictionary, or array and just assign it to a new variable and consume it. Or directly consume it without assigning it.

Harshit Bumb (Appyzie) · Answer

You could use something like this. a!localVariables(
 local!principalAmount: ri!loanAmount,
 local!remainingMonths: ri!tenure - 1,
 local!emi: (
 (local!principalAmount / 100) * ri!interest
 ) / 12,
 {
 { month: 1, emi: local!emi },
 if(
 local!remainingMonths = 0,
 {},
 rule!LoanCalculator(
 loanAmount: local!principalAmount - local!emi,
 tenure: local!remainingMonths,
 interest: ri!interest
 )
 )
 }
)