ppx_deriving_hash

[@@deriving hash]

Deriver for standard hash functions without extra dependencies.

Installation

opam install ppx_deriving_hash

Usage

In dune:

(preprocess (pps ppx_deriving_hash))

Syntax

• Use [@@deriving hash] after a type definition to derive the function val hash: t -> int for it (if the type is named t) or val ty_hash: ty -> int (otherwise if the type is named ty).
• Use [@hash fun x -> ...] after a type expression to override the underlying hash function used for it.
• Use [%hash: ty] as an expression for the hash function of type ty.