Web Development with ReasonML

Interoperating with Objects

Objects are the JavaScript data structure you’ll almost certainly be working with the most. As we discussed in the chapter on records and modules, ReasonML records aren’t objects. However, to interoperate with JavaScript objects, we’ll use a type definition that looks a lot like that of a record.

Consider this JavaScript object, which describes metadata from Papa Parse, a JavaScript module that parses comma-separated value files:

{
  delimiter: // Delimiter used
  linebreak: // Line break sequence used
  aborted:   // Whether process was aborted
  fields:    // Array of field names
  truncated: // Whether preview consumed all input
}

We represent this data type as follows. To make the example a bit clearer, ...