https://github.com/sim642/ppx_deriving_hash

[@@deriving hash]
https://github.com/sim642/ppx_deriving_hash

hacktoberfest ocaml ppx ppx-deriver ppx-extension ppxlib

Last synced: 25 days ago
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[@@deriving hash]

• Host: GitHub
• URL: https://github.com/sim642/ppx_deriving_hash
• Owner: sim642
• License: mit
• Created: 2021-05-21T12:49:53.000Z (over 3 years ago)
• Default Branch: master
• Last Pushed: 2024-08-25T14:50:49.000Z (5 months ago)
• Last Synced: 2024-10-30T05:00:51.039Z (2 months ago)
• Topics: hacktoberfest, ocaml, ppx, ppx-deriver, ppx-extension, ppxlib
• Language: OCaml
• Homepage:
• Size: 40 KB
• Stars: 1
• Watchers: 3
• Forks: 1
• Open Issues: 1
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md
  • License: LICENSE.md

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README

        
# ppx_deriving_hash

## `[@@deriving hash]`

[![ci workflow status](https://github.com/sim642/ppx_deriving_hash/actions/workflows/ci.yml/badge.svg)](https://github.com/sim642/ppx_deriving_hash/actions/workflows/ci.yml)

[![GitHub release status](https://img.shields.io/github/v/release/sim642/ppx_deriving_hash)](https://github.com/sim642/ppx_deriving_hash/releases)

[![opam package status](https://badgen.net/opam/v/ppx_deriving_hash)](https://opam.ocaml.org/packages/ppx_deriving_hash)

Deriver for standard hash functions without extra dependencies.

## Installation

```console

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`.