modernserf

CLU: the Velvet Underground of Programming Languages

Abstract

CLU is the most influential programming language you've never heard of. Many of the basic features of modern programming languages -- such as call-by-sharing, iterators and thrown errors -- first appeared in CLU. How was it made? Why is it so influential? And why isn't it part of our hacker mythology? Let's delve into the history behind CLU and its creator, Barbara Liskov, and discover how this little-known language casts such a long shadow.

Details

The title is a reference to this oft-quoted comment on rock history:

modernserf

// stackify - take function with (a... -> [b]) signature
// return unused stack with results on top
function S (fn) {
  return function* (...args) {
    let iter = this;
    let ln = fn.length - args.length;
    yield* fn.apply(null,args.concat(takeMutable(iter,ln)))
    yield* iter
  }
}

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Interfaces and protocols

ES2015, The newest iteration of JavaScript, introduces a ton of new features, types, and syntactic sugar. Those have all been explored pretty thoroughly, but the one that has the greatest implications for JavaScript are iterators; not the construct in itself but the use of the Iterator protocol.

Iterators are made possible by two new features: symbols and generators. Iterators are not necessarily a feature on their own, but rather a set of conventions around symbols and generators:

Given that JavaScript does not have interfaces, Iterable is more of a convention:

Source: A value is considered iterable if it has a method whose key is the symbol Symbol.iterator that returns a so-called iterator. The iterator is an object that returns values via its method next(). We say: it enumerates items, one per method call.

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Guess Who?

• maybe don't even play the game? have two computer players against each other go very quickly
• what faces do i use? emoji?

Hashtags

Web 2.0

• tags vs categories in blogs
  • tag clouds
• folksonomy

modernserf

; TODO: infix syntax?
; Not everything is a set, but assignment is implicitly to a set.

(def foo 1)
; equivalent to
(def foo (Set 1))

(def foo 1 2)
; equivalent to
(def foo (Set 1 2))

modernserf

"use strict";

import React from "react";
import rebound from "rebound";

const springSystem = new rebound.SpringSystem();

const SpringGroup = React.createClass({
    getDefaultProps (){
        return {

modernserf

function debouncePromise (func, wait){
    var later, boundFn, promise, min = 10;

    var bind = function (fn, ctx, args){
        boundFn = function (done){
            done(fn.apply(ctx, args));
        };
    };

    var reset = function (){ promise = null; };

modernserf

// using asynquence+iterable sequences

var domready;

ASQ()
// wait for `domready` before we proceed
.seq( domready = ASQ.iterable() )
.gate(
	requestJSON( "foo.json" ),
	requestJSON( "bar.json" )

modernserf

Keybase proof

I hereby claim:

• I am modernserf on github.
• I am modernserf (https://keybase.io/modernserf) on keybase.
• I have a public key whose fingerprint is 5D74 D20E 86E2 2415 4BDB F497 CBD8 98BF E95C B0A5

To claim this, I am signing this object:

modernserf

fs = require 'fs'

file_path = __INSERT_FILE_PATH_HERE__

fs.readFile file_path, {encoding: 'utf-8'}, (err, data)->
  # global document object
  doc = {
    tab_size: 2
    lines: data.split("\n")
  }