DDC Meeting on Tuesday 3rd April at Taphouse?

[Ben Lippmeier]

All,

I propose having a DDC / PLT meetup at The Local Taphouse on the afternoon of Tuesday 3rd April, starting about 6pm.

Both Chris and Matthew are actively hacking on DDC as part of their studies, but haven’t met yet. We could talk about our current projects, and also have some beer.

How is the 3rd April? Any other suggestions on the date / place?

If we decide on a date then I’ll also mail an invite to the general FP-Syd list.

Ben.

[Ben Lippmeier]

On Sun., 25 Mar. 2018, 10:35 pm Ben Lippmeier, <be...@ouroborus.net> wrote:

I propose having a DDC / PLT meetup at The Local Taphouse on the afternoon of Tuesday 3rd April, starting about 6pm.

How is the 3rd April? Any other suggestions on the date / place?

On 25 Mar 2018, at 10:51 pm, Chris Hall <followin...@gmail.com> wrote:

I have an appointment until 6:15 in town on the 3rd sorry.

I have no other plans that week (other than work).

How about if we make it later on the 3rd, starting around 7-7:30pm?

Another option might be the Wednesday...

Ben.

[Ben Lippmeier]

We’re having a Discus / DDC meeting next week to talk about the various projects that we’re working on. This is an informal gathering and discussion without pre-prepared talks. All interested parties are welcome. We’ll try to get the room upstairs as we have at previous meetings. Some people will probably arrive a bit earlier, I’m planning to be there 6-6:30pm.

The Local Taphouse
122 Flinders St, Darlinghurst NSW 2010
7pm Tuesday 3rd April.

If you arrive and can’t find us then call Ben Lippmeier +61 421 381 880.

Background: Discus is a Haskell-like language that some of us have been hacking on for a while. DDC is the compiler for it. This is the language formally known as “Disciple”. We changed the name to “Discus” earlier in the year because what we have now looks quite different from what “Disciple” originally was, and "Discus" makes a better logo. More info at http://discus-lang.org/

Cheers,

Ben.

[Ben Lippmeier]

On 28 Mar 2018, at 17:30, Chris Hall <followin...@gmail.com> wrote:

and "Discus" makes a better logo. More info at http://discus-lang.org/

When will we get our Official Discus (TM) shirts?

When someone comes up with a suitably pithy slogan for the reverse side.

I’m also looking for a source of discus fish plush toys...

Ben.

[Tran Ma]

It’s the opposite of a plush, but here’s a glass thing anyway. It belongs on your desk maybe?

On Wed, 28 Mar 2018 at 5:50 pm, Chris Hall <followin...@gmail.com> wrote:

Front:

"I write code in languages you've never heard of"

<Discus fish>

Back:

Discus-lang.org

~ Chris

--

This message was sent from my mobile, please excuse the brevity.

[Ben Lippmeier]

> On 28 Mar 2018, at 7:54 pm, Tim McGilchrist <timm...@gmail.com> wrote:
>
> Is there room for Discuss noobs

Sure, all welcome.

Ben.

[Ben Lippmeier]

> On 28 Mar 2018, at 5:50 pm, Chris Hall <followin...@gmail.com> wrote:
>
> Front:
> "I write code in languages you've never heard of"
> <Discus fish>

An ideal slogan would be somehow related to a core feature of the language, while being suitably cryptic. The Haskell shirt that says “I am the strong, lazy type”, is in the right direction, though AFAIC is a bit close to being a “dad joke” for some potential wearers.

I was thinking along the lines of “Flatten Your Stack”. Discus fish by nature being quite flat, the “stack" referring to the monad stacks of Haskell, and the flattening of which is obtained via the lattice structure of effect types. The main downside I see is that in the current political climate we’d probably be associated with “Full Stack Developers”, which not everyone would be cool with.

Ben.

[Amos Robinson]

"Code à la mode"

<Disco the Discus fish wearing ice-cream cone as party hat>

[Lee Naish]

Haven't been keeping up with developments and won't be at the meeting but...

Ask me if your region is affected

This could affect your region!

Updating your region

On Thu, 29 Mar 2018 09:22 Amos Robinson <amos.r...@gmail.com> wrote:

"Code à la mode"

<Disco the Discus fish wearing ice-cream cone as party hat>

On Thu, 29 Mar 2018 at 07:36 Ben Lippmeier <be...@ouroborus.net> wrote:

--
You received this message because you are subscribed to the Google Groups "Discus" group.
To unsubscribe from this group and stop receiving emails from it, send an email to discus-lang...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

[Ben Lippmeier]

On 28 Mar 2018, at 3:19 pm, Ben Lippmeier <be...@ouroborus.net> wrote:

We’re having a Discus / DDC meeting next week to talk about the various projects that we’re working on. This is an informal gathering and discussion without pre-prepared talks. All interested parties are welcome. We’ll try to get the room upstairs as we have at previous meetings. Some people will probably arrive a bit earlier, I’m planning to be there 6-6:30pm.

Thanks everyone who came to the meeting. Here is a summary.

Attendees (8)

Ben Lippmeier, Matthew Yu, Chris Hall, Richard Collins, Rohan Jacob-Rao, Sean Seefried, Peter Gammie, Trevor McDonell

Sorry if I missed anyone.

Main Changes (since last meeting)

. DDC name changed to Disco Discus Compiler. 

. Name changed because the current system is quite different from the original “Disciple” language described in Ben’s thesis, and Discus fish make a better logo. Disco is the name of the fish (mascot), and partly recalls the quote by SPJ from the paper "Tackling the Awkward Squad”: “In the programming-language world, one rule of survival is simple: dance or die.”

. We now have a new homepage based on the sphinx docs in the main repo.

. Homepage is reachable from http://discus-lang.{org, com,net} with .org being primary.

. Interface files are now stored in binary format via provided by the Shimmer project which has been split into a separate repo. Faster serialisation / deserialisation of interface files improved compile performance by about 30%. Next step is to add an index to the files to avoid deserialising the whole lot when only a few declarations are imported.

. Changed runtime object format to use a uniform 64-bit header for objects, and gave up on maintaining the old 32-bit runtime for now.

. Added try/catch style exception mechanism that allows writing bigger programs more cleanly, though typing is still naive using a non-maskable ‘Error’ effect.

. Added floating point primitives so we can write real numeric programs like ray tracers etc (demo in the repo)

. Added global# primitive to Salt language that allows new global runtime system variables to be defined easily.

. Added more library support, specifically basic file handling and a JSON parser. Doing this forced out some bugs in compilation of pattern matching.

Main Holes

. Compile time performance is still poor due to need to deserialise all interface files for transitively imported modules. This is being addressed as part of the memoization project (described below)

. Use of a single global namespace is a headache. The base library is starting to become large enough that new declarations are likely to clash with existing ones, which is hard to keep track of manually.

Active Projects

Chris: Adding a capability system to ensure that concurrent effectful computations do not interfere. 

Matthew: Adding support for a version of compact regions, which allows data to be allocated into a region separate from the heap and not traced during main GC cycles. Doing this should reducing pause times and improving cache locality for access to data in the compact region.

Ben + Trevor: Adding a reflection and memoization system so that results of computations can be stored between runs of a program. Work on this will also contribute to reducing compile times, as we can use the same indexed file format for interface files as we use to store memoized values.

Decisions

. We’ll move to having meetings every 3 months while there are multiple active local projects. Next meeting would be in July, perhaps July 10th though this will be confirmed closer to the date.

Cheers,

Ben.