# Validation Scripts

By

Travis Horn

Lecture 2, Part 5

Lecture Video

Two modules are provided: Homework01.hs and Homework02.hs.

The redeemer has been changed to a pair of Bools. Validation should only succeed if they match.

Homework code

My solution

Before fixing it, the validator in the homework code always passes.

mkValidator _ _ _ = True -- FIX ME!

The correct validator can be written like so:

mkValidator _ (x, y) _ = traceIfFalse "Redeemer booleans do not match" $ x == y

Additionally, the homework code had a broken type instance and broken validator, valHash, and scrAddress definitions. These are mostly boilerplate that could be easily copied from the working examples written earlier in the lecture.

It's the same as Homework 1 except the redeemer is a custom type called MyRedeemer that has two fields called flag1 and flag2 that are just Bools.

Homework code

My solution

Since the redeemer is a custom type that looks like this:

data MyRedeemer = MyRedeemer
    { flag1 :: Bool
    , flag2 :: Bool
    } deriving (Generic, FromJSON, ToJSON, ToSchema)

The correct validator can be written like so:

mkValidator _ (MyRedeemer x y) _ =
  traceIfFalse "Redeemer booleans do not match" $ x == y

And again, the homework code had broken boilerplate that could be copied from working examples written earlier in the lecture.