Module AbtSource

Overview

um-abt is a library for representing and manipulating the the syntax of languages that use variables.

um-abt provides abstract binding trees (ABTs). An abstract binding tree is an abstract syntax tree, enriched with constructs to manage variable binding and scope.

um-abt also supports unification over ABTs.

Example

A typical example of a module satisfying this interface, used to represent the syntax of the untyped lambda calculus:

  module O = struct
    type 'a t =
      | App of 'a * 'a
      | Lam of 'a
    [@@deriving eq, map, fold]

    let to_string : string t -> string = function
      | App (l, m) -> Printf.sprintf "(%s %s)" l m
      | Lam abs    -> Printf.sprintf "(λ%s)" abs
  end

  include Abt.Make (O)

Note the use of ppx_deriving to derive most values automatically.

Interfaces

Top-level modules