ReasonML Quick Start Guide

Helper functions

Since url.path of ReasonReact.Router is a list of strings, and our Router.route.href is a string, we need a way to convert from string to a list of strings:

let hrefToPath = href =>  Js.String.replaceByRe([%bs.re "/(^\\/)|(\\/$)/"], "", href)  |> Js.String.split("/")  |> Belt.List.fromArray;

We'll discuss Reason's pipe operator (|>) and JavaScript interoperability in Chapter 4, BuckleScript, Belt, and Interoperability.

We also need a way to convert a url to a route for use in initial state, as well as within the callback function of watchUrl:

let urlToRoute = (url: ReasonReact.Router.url) =>  switch (    Belt.List.getBy(routes, route => url.path == hrefToPath(route.href))  ) {  | None => Belt.List.headExn(routes) | Some(route) => ...