In this lesson we're adding a repayment function along with a state variable to store important loan information. By the end of this unit, the contract will only be capable of managing a single loan -- we'll add the capacity to track several user loans in the next unit on hashmaps.
This lesson introduces the struct datatype to manage loan parameters. Structs somewhat resemble Python objects, in that they can contain disparate data types which are readily accessible.
Our solution will use a struct to track loan parameters including the following:
struct Loan:
liquidation_price: uint256
deposit_amount: uint256
In the script, we create a state variable open_loan instantiated as a Loan struct
open_loan: public(Loan)
We can now instantiate the variable using the following syntax. The solution file does so in the following fashion:
self.open_loan = Loan({liquidation_price: liq_price, deposit_amount: quantity})
Now the properties of the struct are easy to access. One could easily return the liquidation price using the following::
return self.open_loan.liquidation_price