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/ "Apter trees" http://archive.vector.org.uk/art10500340
/ https://github.com/stevanapter/hypertree#concepts
/ http://nsl.com/k/treetable/treetable_k3.html
/ http://www.nsl.com/k/trees.k
/ John Earnest notes https://github.com/JohnEarnest/ok/blob/gh-pages/docs/Trees.md
/ Aaron Hsu talk on high-performance tree wrangling https://www.youtube.com/watch?v=hzPd3umu78g
  / https://www.dyalog.com/uploads/conference/dyalog18/presentations/U19_Tree_Wrangling_the_APL_Way.pdf
/ Translation into k by JE: https://github.com/JohnEarnest/ok/blob/gh-pages/examples/key.k
/ Conquering recursion: http://archive.vector.org.uk/art10501740
/ https://news.ycombinator.com/item?id=21680133 - comments from geocar and John Earnest

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// https://twitter.com/ua6oxa/status/1170457046153650176
"use strict";

function evalInContext(env, code) {
  const
    s = JSON.stringify,
    locals = Object.keys(env),
    keys = locals.map(function(k){return s(k)}),
    values = locals.map(function(k){return env[k]}),
    body = s("return eval(" + code + ")")

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// Inspired by http://kparc.com/b/c.h
// See also https://chat.stackexchange.com/transcript/message/51402407#51402407

const x="x",y="y"

// Function makers
function fn() {return new Function(...arguments)}
function f0(b) {return fn(b)}
function f1(b) {return fn(x,b)}
function f2(b) {return fn(x,y,b)}

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Official site (kparc.com)

• Summary
• Example programs
• Updated (?) edit.k
• ~2014 older version that has more info
• The project has been running since at least 2012

Articles

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// OPTION A: Nest value and coords within same obj

_CELLS = {
    a: {
        v: 123,
        l: "B2"
    },
    b: {
        get v() {return a * 2},
        l: "B3"

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/* Caveats:
- The below code assumes we have access to the consumed sheet's _CELLS object. Unclear how that would be established (c+p?).
- Will somehow need to deal with accessing cells in topological order. We record this when a sheet is run - maybe we can use that?
- Unclear whether/how we will import sheet boilerplate fns (maybe a good idea to move it to a dedicated _BOILERPLATE object...)
*/

var _CELLS = {
    a: 123,
    get b() {return a * 2}
}

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// Balancing speed and concision, with a preference for speed. Can we do better?
// No ES6! Mesh is ES5-compatible.

// Added to global namespace by calling the following:
// g._defFunctions = function()  {for (let k in _FUNCTIONS) g[k] = _FUNCTIONS[k]}

// Vanilla
const _FUNCTIONS = {
    SUM: function() {
        const l=arguments.length,f=function(x,y){return x+y};

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'use strict';
const _CELLS = {
    B2: ({
      l: [1,1],

      n: false,
      get v() {
          return `{"some": "simple value", "another": "simple_value", "nested": [1, 2, 3], "obj": {"hello": "world!", "it's": "me"}}`;
      }
    }),

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// 1. Array literals don't have a way to set getters, which are essential for self-references
// They *do* work if you manage them directly, but this produces source code that's difficult to manage.
const arr = [1];
Object.defineProperty(arr, '1', {get: function() {return this[0] + 1}})
console.log(arr[1]) // prints 2
arr[0] = 1234;
console.log(arr[1]) // prints 1235

// 2. Objects literals don't have a key order, which is essential for self-refences to preceding values.
// (You could *potentially* mimic this by making an object literal with keys that are numbers that has __proto__ = Array.prototype,

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// https://en.wikipedia.org/wiki/Delimiter#ASCII_delimited_text
const FS = String.fromCharCode(28); // File separator; end of file. Or between a concatenation of what might otherwise be separate files.
const GS = String.fromCharCode(29); // Group separator; between sections of data. Not needed in simple data files.
const RS = String.fromCharCode(30); // Record separator; end of a record or row.
const US = String.fromCharCode(31); // Unit separator; between fields of a record, or members of a row.

function print_to_string_table(str) {
    let o = "";
    for (var i = 0; i < str.length; i++) {
        const char = str[i];