akabe’s gists

akabe / find2d_bl.py

Last active June 27, 2024 09:31

Find2D-BL アルゴリズムの実装

	# An implementation of Find2D-BL.
	#
	# Shinji Imahori, Yuyao Chien, Yuma Tanaka, and Mutsunori Yagiura.
	# Enumerating bottom-left stable positions for rectangle placements with overlap.
	# Journal of the Operations Research Society of Japan. Vol.57, No.1, March 2014, pp.45--61.
	# https://www.jstage.jst.go.jp/article/jorsj/57/1/57_KJ00009350944/_article/-char/ja/

	from __future__ import annotations

	from dataclasses import dataclass

akabe / bucklescript_headless_chrome.ml

Last active January 11, 2018 04:45

A short example of bindings of `chrome-launcher` and `chrome-remote-interface` in OCaml BuckleScript

	(* This is a short example of bindings of `chrome-launcher` and `chrome-remote-interface`
	(for node libraries manipulating headless-mode Google Chrome) in OCaml BuckleScript (https://bucklescript.github.io/).

	Usage:
	$ npm install -g chrome-launcher chrome-remote-interface
	$ bsc -bs-main bucklescript_headless_chrome.ml
	Headless browsers (such as PhantomJS, Chrome, Firefox) are useful for, e.g.,

	- integration tests of JavaScript products on a real browser, or
	- Web scraping for pages containing complex JavaScript.

akabe / install_opam.sh

Last active October 12, 2018 02:43

OPAM/OCaml scripts for CI

	#!/usr/bin/env sh -xeu

	##
	## Usage:
	## curl -sL https://gist.githubusercontent.com/akabe/24979afbf95c4cf4393f589cda997e1b/raw/install_opam.sh \| sh -xeu
	##
	## Variables:
	## - $OPAM_PREFIX Path to install opam
	## - $OPAM_VERSION Version of OPAM to be installed
	## - $OCAML_VERSION Version of OCaml to be installed

akabe / centos-zmq.sh

Created July 28, 2017 03:41

Install zeromq-devel on CentOS7

	#!/bin/sh -xeu

	sudo yum install -y epel-release
	sudo yum install -y zeromq-devel

akabe / extensible_record_by_lens.ml

Last active September 4, 2019 01:43

Extensible record by Lens trick in OCaml

	(** The Lens trick: getter and setter for fields *)
	type ('s, 'v) lens =
	{
	get: 's -> 'v;
	set: 'v -> 's -> 's;
	}

	let id_lens = {
	get = (fun x -> x);
	set = (fun v _ -> v);

akabe / SafeList.scala

Last active June 24, 2016 00:48

A simple example of type-safe head, tail, and zip of List by Peano-style type-level natural number via phantom type in Scala

	object SafeList {
	trait Z // phantom type "zero" (corresponding to 0)
	trait S[N] // phantom type "successor" (correspoding to n => n+1)

	class SList[N, E] private[SafeList] (private[SafeList] val list: List[E])
	// SList[N, E] is a list of elements of type E, and length N.

	def empty[E] = new SList[Z, E](Nil)
	def cons[N, E] (x: E, xs: SList[N, E]) = new SList[S[N], E](x :: xs.list)

akabe / subtyping2.ml

Created November 19, 2015 11:39

A subtyping encoding by phantom types

	open Format

	(** The types of the source language
	(Hindley-Milner + subtyping + bounded polymorphism) *)
	module SL =
	struct
	type 'a typ =
	\| Base of 'a (** base type *)
	\| Var of string (** type variable *)
	\| Arrow of 'a typ * 'a typ (** function type *)

akabe / subtyping1.ml

Last active November 22, 2015 06:51

A subtyping encoding by phantom types [Fluet and Pucella, JFP 2006]

	open Format

	(** The types of the source language
	(Hindley-Milner + subtyping + bounded polymorphism) *)
	module SL =
	struct
	type 'a typ =
	\| Base of 'a (** base type *)
	\| Var of string (** type variable *)
	\| Arrow of 'a typ * 'a typ (** function type *)

akabe / generative_phantom_type_first_class_polymorphism.ml

Created October 29, 2015 07:19

Static size checking for lists (loaded from files) by generative phantom types (first-class-polymorphism version)

	(* http://akabe.github.io/2015/10/GenerativePhantomTypes *)

	#load "str.cma";;

	(** Loads a list of integers from a file of a given path (delimiters = spaces,
	tabs, or line feeds). *)
	let load_list fname =
	let re = Str.regexp "[ \t]+" in
	let oc = open_in fname in
	let rec aux acc = try aux (input_line oc :: acc) with End_of_file -> acc in

akabe / generative_phantom_type_GADT.ml

Created October 29, 2015 07:06

Static size checking for lists (loaded from files) by generative phantom types (GADT version)

	(* http://akabe.github.io/2015/10/GenerativePhantomTypes *)

	#load "str.cma";;

	(** Loads a list of integers from a file of a given path (delimiters = spaces,
	tabs, or line feeds). *)
	let load_list fname =
	let re = Str.regexp "[ \t]+" in
	let oc = open_in fname in
	let rec aux acc = try aux (input_line oc :: acc) with End_of_file -> acc in

Akinori ABE akabe