David Peter sharkdp

Type-safety in physics calculations

This article describes a (loose?) analogy between physical units and data types in programming languages that I thought about while working on Insect, a scientific calculator that supports physical units.

In addition to typical mathematical operators like +, *, ^, %, etc., Insect has a special conversion operator (written as an arrow ->/➞ or as the word to). It can be used to convert an expression to a particular unit:

≫ 2 ft + 2 in ➞ cm

  = 66.04 cm

	#include <iostream>

	struct todo_statement {
	public:
	todo_statement(const char* file, const int line)
	: m_file(file), m_line(line) {}

	template <typename T>
	operator T() {
	std::cerr << "Error: Remove todo() statement in " << m_file << ":" << m_line

	echo "int main() {}" > just-exit.c
	gcc -O just-exit.c -o just-exit-c

	echo "" > just-exit.py

	echo "fn main() {}" > just-exit.rs
	rustc -O just-exit.rs -o just-exit-rs

	echo "" > just-exit.rb

	# Configuration for Alacritty, the GPU enhanced terminal emulator


	# Any items in the `env` entry below will be added as
	# environment variables. Some entries may override variables
	# set by alacritty it self.
	env:
	# TERM env customization.
	#
	# If this property is not set, alacritty will set it to xterm-256color.

	// Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT
	// file at the top-level directory of this distribution and at
	// http://rust-lang.org/COPYRIGHT.
	//
	// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
	// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
	// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
	// option. This file may not be copied, modified, or distributed
	// except according to those terms.

	#!/usr/bin/python

	import argparse
	import json
	import matplotlib.pyplot as plt

	parser = argparse.ArgumentParser()
	parser.add_argument("results", help="JSON file with benchmark results")
	args = parser.parse_args()

	#!/bin/bash

	# the root directory for the search
	base_path="$HOME" # CHANGE THIS

	if ! which bench > /dev/null 2>&1; then
	echo "'bench' does not seem to be installed."
	echo "You can get it here: https://github.com/Gabriel439/bench"
	exit 1
	fi

	#!/bin/bash

	trap "tput reset; tput cnorm; exit" 2
	clear
	tput civis
	lin=2
	col=$(($(tput cols) / 2))
	c=$((col-1))
	color=0
	tput setaf 2; tput bold

	echo "This script will now ask for your password in order to gain root/sudo"
	echo "permissions. These are required to reset the harddisk caches."
	echo ""

	sudo echo "Okay, acquired superpowers :-)" \|\| exit

	base_path="/mnt/daten"
	pattern='.*[0-9]\.jpg$'

	for _ in $(seq 1 3); do

	#pragma once

	extern double pi;