Dynamic records

This library enables you to define and manipulate dynamic records in OCaml.

Example

Let us define a "point" record with three integer fields: x, y and z.

First, declare a new record layout. It uses a phantom type so that point has type point layout.

type point
let point : point Record.layout = Record.declare "point"

Second, define the fields. They have the type (int, point) field.

let x = Record.field point "x" Type.int
let y = Record.field point "y" Type.int
let z = Record.field point "z" Type.int

Third, "seal" this record structure. This prevents it from being further modified. Structures must be sealed before they can be used.

let () = Record.seal point

At this point, you have a working record structure. The next step is to create actual records. They have the type point Record.t and are created using Record.make. Initially their fields have no value.

let _ =
  let p = Record.make point in
  Record.set p x 3;
  Record.set p y 4;
  Record.set p z 5;
  Record.format Format.std_formatter p

The last line outputs:

{"x":3,"y":4,"z":5}

Licensing

This library is available under the 2-clause BSD license. See COPYING for more information.

yallop/records

Dynamic records

Example

Licensing