ZEzeckalpha·Mar 6, 2013
I've played around with roy. Good to see it getting some press!
More on topic, what about Contract DD as an alternative to Test DD and Type DD? e.g. https://github.com/disnet/contracts.coffee
In Where TDD Failsdisnet
contracts.coffee
JavaScript2011–2013
disnet / contracts.coffee
contracts.coffee
Contracts for CoffeeScript
4Distinct people
4Mentions
0Explicit recommenders
217GitHub stars
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Contracts for CoffeeScript
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This week on Hacker News
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Mentions over time
HN mentions by month4 dated mentions
Observed mentions: 2011-08-30 01:49:50 UTC to 2013-03-06 00:50:56 UTC.
Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.
View mention counts and date ranges
| Period | Start (UTC) | End (exclusive, UTC) | Mentions | Submissions | Comments |
|---|---|---|---|---|---|
| Aug 2011 | 2011-08-01 00:00:00 UTC | 2011-09-01 00:00:00 UTC | 2 | 0 | 2 |
| Sep 2011 | 2011-09-01 00:00:00 UTC | 2011-10-01 00:00:00 UTC | 0 | 0 | 0 |
| Oct 2011 | 2011-10-01 00:00:00 UTC | 2011-11-01 00:00:00 UTC | 0 | 0 | 0 |
| Nov 2011 | 2011-11-01 00:00:00 UTC | 2011-12-01 00:00:00 UTC | 0 | 0 | 0 |
| Dec 2011 | 2011-12-01 00:00:00 UTC | 2012-01-01 00:00:00 UTC | 0 | 0 | 0 |
| Jan 2012 | 2012-01-01 00:00:00 UTC | 2012-02-01 00:00:00 UTC | 1 | 1 | 0 |
| Feb 2012 | 2012-02-01 00:00:00 UTC | 2012-03-01 00:00:00 UTC | 0 | 0 | 0 |
| Mar 2012 | 2012-03-01 00:00:00 UTC | 2012-04-01 00:00:00 UTC | 0 | 0 | 0 |
| Apr 2012 | 2012-04-01 00:00:00 UTC | 2012-05-01 00:00:00 UTC | 0 | 0 | 0 |
| May 2012 | 2012-05-01 00:00:00 UTC | 2012-06-01 00:00:00 UTC | 0 | 0 | 0 |
| Jun 2012 | 2012-06-01 00:00:00 UTC | 2012-07-01 00:00:00 UTC | 0 | 0 | 0 |
| Jul 2012 | 2012-07-01 00:00:00 UTC | 2012-08-01 00:00:00 UTC | 0 | 0 | 0 |
| Aug 2012 | 2012-08-01 00:00:00 UTC | 2012-09-01 00:00:00 UTC | 0 | 0 | 0 |
| Sep 2012 | 2012-09-01 00:00:00 UTC | 2012-10-01 00:00:00 UTC | 0 | 0 | 0 |
| Oct 2012 | 2012-10-01 00:00:00 UTC | 2012-11-01 00:00:00 UTC | 0 | 0 | 0 |
| Nov 2012 | 2012-11-01 00:00:00 UTC | 2012-12-01 00:00:00 UTC | 0 | 0 | 0 |
| Dec 2012 | 2012-12-01 00:00:00 UTC | 2013-01-01 00:00:00 UTC | 0 | 0 | 0 |
| Jan 2013 | 2013-01-01 00:00:00 UTC | 2013-02-01 00:00:00 UTC | 0 | 0 | 0 |
| Feb 2013 | 2013-02-01 00:00:00 UTC | 2013-03-01 00:00:00 UTC | 0 | 0 | 0 |
| Mar 2013 | 2013-03-01 00:00:00 UTC | 2013-04-01 00:00:00 UTC | 1 | 0 | 1 |
What Hacker News says
4 sources> Indeed it would be. That said, CoffeeScript is a compiler of sorts.
The fact that we have a compiler doesn't give us all that much. Adding types to a dynamic language (where things can be monkey patched, evaled, and just generally mutated willy-nilly) is a hard problem (not impossible but definitely research [1 and 2 to start, but much more]).
>> And we'd like to do it in a more elegant way than constantly writing "if(argument === ...) then ... else ..."
> This doesn't really seem to solve that problem.
It solves the problem of elegance :)
> It just throws consistent errors if the types don't match. Your code would likely throw its own error if you didn't check the type manually. In my experience, native js errors are as easy or easier to track down that throwing errors yourself.
Key word there is likely. Like I mentioned, there are som
Read the rest
e errors that don't result in a run-time error and we might like to check for those too. As a silly example, consider a binary search tree [3] that you want to keep balanced. If you get the balance wrong, there's no immediate fault (no TypeError/NPE).
> Ah, ok. That makes more sense. They're like python decorators, only single purpose.
I guess you could say that. If we had an expressive enough decorator-like system for CoffeeScript we could probably implement contracts with it. CS doesn't have one of course so path of least resistance is to add the contract language extension directly.
[1] http://ecee.colorado.edu/~siek/blame-forall-2011.pdf
[2] http://dl.acm.org/citation.cfm?id=1863561
[3] https://github.com/disnet/contracts.coffee/blob/master/test/...
ok, figured out that it takes care of the existing prototype operator (::) in lexing [1],[2]. It seems little annoying but guess I'll get the hang of it.
[1] https://github.com/disnet/contracts.coffee/blob/master/src/l...
[2] https://github.com/disnet/contracts.coffee/blob/master/src/l...
In Contracts For CoffeeScript