LICENSE

Copyright (c) 2015 Robert Nystrom

---------------------------------- Commentary ----------------------------------

The licensing story for this repository is a little complex. Here's my
motivation:

* I want you to get as much use out of the material here as possible. I wrote
  this book to help you, and I don't want you to be encumbered when it comes to
  making the most of it. That's also why I put it online for free.

* With my previous book, collaboration on GitHub was immesensely helpful. I want
  to ensure people can fork the repo, send me fixes, etc. without violating the
  license or feeling weird.

* When it comes to code, I'm completely comfortable with people redistributing,
  remixing, changing, whatever with it. I've been using the MIT license for open
  source stuff for decades.

  This book contains two complete interpreters and I would be delighted for them
  to be the jumping-off point for any number of real full-featured language
  implementations.

* When it comes to my prose and the visual design of the site, that feels a
  little more, I don't know, *me* than the code. The words are in my voice, and
  the look of the site is part of its and, by extension, my brand.

  I feel weird thinking about someone, say taking one of the chapters and making
  significant changes to it to fit their writing style while still having some
  of it read like it came from me. Likewise, I'd be sad to see another site
  online that looked exactly like mine because it reuses my stylesheets.

* My previous book ended up being translated into several languages. I want to
  be careful to not be so permissive that it prevents me from signing typical
  contracts that give them exclusive translation rights to certain territories
  and languages.

* If I allow the prose to be redistributed commercially, there is nothing
  preventing someone from slapping together a cheap print or ebook version of
  the book and putting it up for sale. I'm not too worried about my own sales
  being undercut, but I very much want to avoid readers finding themselves with
  a low quality book that they incorrectly think is from me.

  I worked very hard on this book. I want you to get the best possible
  experience.

All of this is way more complex than I'd like, especially since my brain isn't
wired to care about intellectual property. I like thinking about making stuff,
not thinking about the legal rights around the stuff I made. (If your brain is
wired to think about legal stuff and you see that I'm doing something dumb,
please do let me know.)

The best solution I've been able to come up with is to use two licenses:

---------------------------------- License(s) ----------------------------------

Each file in this repository falls under one of two licenses. Files whose
extension is ".html", ".scss", ".css", ".md" (except for "book/appendix-i.md"
which uses the MIT license below), and ".txt" use this Creative Commons license:

    Attribution-NonCommercial-NoDerivatives 4.0
    International (CC BY-NC-ND 4.0)

    https://creativecommons.org/licenses/by-nc-nd/4.0/

All other files, including (but not limited to) ".c", ".dart", ".h", ".java",
and ".lox" use the MIT license:

    Permission is hereby granted, free of charge, to any person obtaining a copy
    of this software and associated documentation files (the "Software"), to
    deal in the Software without restriction, including without limitation the
    rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
    sell copies of the Software, and to permit persons to whom the Software is
    furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included in
    all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
    IN THE SOFTWARE.