Page.re

module Page = {
  type action =
    | NoOp;
  type ledger = {
    id: string,
    statementId: string,
    actor: string,
    influencer: string,
    referenceType: string,
    paymentId: string,
    amount: string,
    timestamp: int
  };
  type state = { items: list(ledger) };
  let component = ReasonReact.reducerComponent("PageSearch");
  let make = _children => {
    ...component,
    initialState: () => { items: [] },
    reducer: (action, _state: state) =>
      switch (action) {
      | NoOp => ReasonReact.NoUpdate
      },
    render: _self =>
      <div>
        <div className="search-bar-container">
          <table className="ledger"> <TableHeader /> </table>
        </div>
      </div>
  };
};

let render = root => ReactDOMRe.render(<Page />, root);

I added the reducer definition, yet still receiving the same error.

  We've found a bug for you!
  /~~project-path~~/reason-react-prototype/src/TransactionList.re 56:40-47
  
  54 │ };
  55 │ 
  56 │ let render = root => ReactDOMRe.render(<Page />, root);
  
  Is this a ReasonReact reducerComponent or component with retained props?
  If so, is the type for state, retained props or action declared _after_ the component declaration?
  Moving these types above the component declaration should resolve this!
  
  Here's the original error message
  This has type:
    ReasonReact.componentSpec
    (Page.state,  Page.state,  ReasonReact.noRetainedProps, 
      ReasonReact.noRetainedProps,  Page.action)
  But somewhere wanted:
    ReasonReact.component (Page.state,  'a,  'b) (defined as
      ReasonReact.componentSpec (Page.state,  Page.state,  'a,  'a,  'b))
  The type constructor Page.state would escape its scope
  
ninja: build stopped: subcommand failed.

Thanks to the very helpful hello123#8705 on the ReasonML discord channel, I learned that you have to annotate the state variable so that the program will compile.