Reactive programming again

Two little JS frameworks: ripple.js, which aims to be tiny, and "React.js and Bacon", a look at another way to do reactive stuff.

Coursera courses in functional programming and reactive programming

I might do these...

Functional programming in Scala, reactive programming in Scala.

Reactor.js

Reactive programming in JavaScript.

Responding to excessive volume

A neat little discussion at StackOverflow (superuser) about how to take an action when the microphone volume goes too high, with some really fascinating responses, including one cobbling it together with Pure Data, an open source visual programming language I'd never heard of.  (It's a dataflow thing.)

Sirea

Wow!  Sirea is a Haskell framework for Reactive Demand Programming - tl;dr of that being "better Excel".  Kind of where I've wanted to go for years with dataflow programming, long before I got entangled with Decl.

But the Sirea project has immense amounts of ramifying thought behind it, to the extent that it must be made part of the Decl canon.

Rx: reactive extensions to .NET and JS

So Rx is a reactive extension library that brings reactive programming to the .NET world, built on top of LINQ, which I'd also like to look at - and Microsoft just open sourced it.

• Blog post about this.
• HNN thread.
• The repository.
• Rx koans, also at CodePlex.
• Intro to Rx, an ebook for learning the thing that really looks quite fascinating.

It seems to me that reactive extensions are a natural outgrowth of lazy lists (plus an event subscription model for new additions to the list) and I could profitably bring them to Perl based on Data::Table::Lazy.  Just a thought.

I feel as though I'm recapitulating a lot of the pieces of Decl, only in standalone form.  This feels like a good thing - in the end, Decl will be just syntactic sugar on a lot of powerful tools, which is where it should have been in the first place (I just wasn't finding the tools I wanted).

Functional Reactive Programming

This is really a neat idea that I've mentioned before, but reactive programming is the idea of setting up a network of values (Elm calls these signals - values that change over time) that affect one another dynamically.  This is an inherently declarative style of programming (as the second link there explicitly states).

On that same site, there's an excellent exposition of how to write a Pong game in Elm using this programming style, and a more recent article on how reactive programming avoids the proliferation of callbacks that characterize API-style and more recent non-blocking frameworks like node.js.

Elm itself is a language that compiles to JavaScript on the browser and (I think) on the server as well.  It seems to have some way to integrate with Haskell on the server, but I honestly haven't spent much time investigating it - and I should. I should investigate all the things.

Reactive programming

Here's a term I hadn't seen before: reactive programming. Reactive programming is a declarative style in which relationships between values are defined, then changes to one value propagate to the other. A data flow graph is created, in other words. I've been stumbling towards this in Decl, of course, but here's Elm, a type-safe functional reactive programming language that compiles to JavaScript.

Apparently, there's nothing that can't be done in JavaScript these days.

I personally find this code nearly unreadable (I'm sure I'd improve with some practice), but the notion of declarative specification of JavaScript I see in the examples is utterly enthralling.