Data.IO, CoffyScript, Circular Progress

Alex R. Young





libraries canvas browser coffeescript ES6

Data.IO, CoffyScript, Circular Progress

Posted by Alex R. Young on .

libraries canvas browser coffeescript ES6

Data.IO, CoffyScript, Circular Progress

Posted by Alex R. Young on .


Data.IO (GitHub: scttnlsn / data.io, License: MIT, npm: data.io) by Scott Nelson is a library for bidirectional syncing over Socket.IO. It has server-side resources which encapsulate logic and persistence. Resources are stacks of composable middleware functions that sync client requests. The client-side component is comparatively lightweight -- it's lower-level than Backbone.js, so I suspect it could be used with any data binding library.

Data.IO allows you to keep core business logic on the server, while easily subscribing to data in the client. It's a bit like Backbone.js and Express, but purpose-built for working with data syncing.


CoffyScript (GitHub: loveencounterflow / coffy-script) by "loveencounterflow" is a port of CoffeeScript that adds support for yield from ES6:

If you have never programmed with iterators and generators, you may imagine as a 'resumable return' for starters. For the more technically oriented, ES6 defines generators as "First-class coroutines, represented as objects encapsulating suspended execution contexts (i.e., function activations)." Well, maybe 'resumable return' is not so bad after all.

# Using a star after the arrow 'licenses' the use of `yield` in the function body;
# it basically says: this is not an ordinary function, this is a generator function:
count = ->*  
  yield 1
  yield 2
  yield 3

# Calling a generator function returns a generator:
counting_generator = count()

# Now that we have a generator, we can call one of its methods, `next`:
log counting_generator.next()   # prints: { value: 1, done: false }

# ...and we can go on doing so until the generator becomes exhausted:
log counting_generator.next()   # prints: { value: 2, done: false }  
log counting_generator.next()   # prints: { value: 3, done: false }  
log counting_generator.next()   # prints: { value: undefined, done: true }  
log counting_generator.next()   # throws an error saying "Generator has already finished"  

The documentation in the readme is thorough, and explores various aspects of working with yield. For example: How Not to Yield to Callback Hell: Serializing Control Flow.

Circular Progress

Circular Progress

Circular Progress (GitHub: neoziro / circular-progress, License: MIT, bower: circular-progress) by Greg Bergé is a progress widget with no dependencies. Given a Canvas element, it'll show a circular representation of a process's progress:

var progress = new CircularProgress({  
  radius: 70,
  strokeStyle: 'black',
  lineCap: 'round',
  lineWidth: 4