Why do I need to indent so much when constructing (not creating) a contract?

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I seem to need at least 5 spaces when indenting a with block in constructing a contract.

For example:

template Person
  with
    owner : Party
    name : Text
    dateOfBirth : Date
  where
    signatory owner

test = scenario do
  alice <- getParty "Alice"
  let person = Person with
        owner = alice
        name = "Alice"
        dateOfBirth = date 2020 Jan 1

  person.name === "Alice"

If I dedent the with block, so it looks like this:

  let person = Person with
      owner = alice
      name = "Alice"
      dateOfBirth = date 2020 Jan 1

Then I get the following error:

    • Constructor ‘Person’ does not have the required strict field(s): owner,
                                                                       name, dateOfBirth
    • In the expression: Person {}
      In an equation for ‘person’: person = Person {}

It appears as if the parser is recognizing nothing inside the with block.

If I go down to 2 spaces, I get an error on the first =:

    parse error on input ‘=’

Why do I need so much whitespace?

You need to indent further than the name of the variable you are defining in your let. In

let person = Person with
    owner = alice

you are defining 2 let-bindings, person is bound to Person with (so no fields which is why you are getting the error) and owner is bound to alice.

Thanks @cocreature! I didn’t realize I could define multiple values in a single let.