Grid.re

module Grid = {
  module type Grid = {type t;};

  type t = {
    rowNames: list(string),
    columnNames: list(string),
    data: array(array(string)),
  };

  let make = (~rowNames, ~columnNames): t => {
    rowNames,
    columnNames,
    data:
      Array.make_matrix(
        List.length(rowNames),
        List.length(columnNames),
        "",
      ),
  };
};

Index.re

let grid = Grid.Grid.make(~columnNames, ~rowNames);
Js.log(grid.data); /* surely this shouldn't be allowed??? */