5 ms·

PureScript 0.13 Release

90 points by valb 7y ago

jjnoakes 7y ago
I noticed a few languages removing support for octal and binary literals. I wonder why. I find them useful and the parser overhead seems minimal to keep them around.
- wtetzner 7y ago
  Yeah, it never made sense to me not to include those, given how simple it is.
  - marquis-chacha 7y ago
    The typical octal literal syntax I've seen uses a 0 prefix. This gives rise to quite a few gotchas, as most people think of leading 0's as being non-value-changing. Maybe 0o12345670?
    - wtetzner 7y ago
      Yeah, I agree that it's not a good syntax. I do think 0o is a good prefix though.
- ergothus 7y ago
  Generally developers tend to either (1) misunderstand them when they encounter them in the wild or (2) accidentally invoke them. (I believe multiple languages have had issues with '04' being treated as an octal, which works fine and doesn't trigger developer notice until they encounter '09' in the wild). Whether these are VALID concerns I won't take a stance on - just saying these are the reasons I've seen cited.
  - wtetzner 7y ago
    Why not use 0x,0b, and 0o for hex, binary, and octal literals? I never liked the fact that a number starting with 0 was treated as octal.
    - steinuil 7y ago
      OCaml does just that; it might have been the first language to have 0b and 0o prefixes for binary and octal literals. https://discuss.ocaml.org/t/the-origin-of-the-0b-01-notation/3180 https://discuss.ocaml.org/t/the-origin-of-the-0b-01-notation...
- natefaubion 7y ago
  We found no usages of it in the wild. If there is real-world need for them, we'll consider adding them back.
  - scrollaway 7y ago
    FWIW I use binary literals a bunch in python, either when working with binary file formats or with bitfields.
    - natefaubion 7y ago
      Yes, I'm not saying there aren't usages for them in general, but PureScript currently occupies a niche that doesn't get down to the level of binary file formats. This change is more about "only supporting what we need to right now", rather than "we don't like binary literals". As noted elsewhere, it's not difficult to add support for them when we need to.
Scarbutt 7y ago
What happened to the original author of PS? https://github.com/purescript/purescript/graphs/contributors https://github.com/purescript/purescript/graphs/contributors
- dwhitney 7y ago
  Like many of us, he had children and couldn't keep up with the workload, so he took a step back. Fortunately there is a very active community working on PureScript!
- gb 7y ago
  Life! :) He still uses PS and chimes in on some issues, but doesn't really have time to work on the compiler anymore: https://twitter.com/paf31/status/941745900426215424 https://twitter.com/paf31/status/941745900426215424
- kepano 7y ago
  I don't speak for Phil, but I do work with him at Lumi where we use PureScript for almost all frontend. It's been really fun to show that PureScript can be used successfully in production. You can see some of our tutorials and open source projects here: https://www.lumi.dev https://www.lumi.dev
dmitryminkovsky 7y ago
Are there other languages that make an opinion on tabs/spaces? This seems nice. > The only whitespace now allowed in code is ASCII space and line endings. Since you must use indentation to format PureScript code (unlike Haskell), we felt it was best to be more restrictive in what you can write instead of allowing potentially confusing behavior (implicit tab-width, zero-width spaces, etc). You can still use unicode whitespace within string literals. I’m also wondering about the removed literals.
- nathanyukai 7y ago
  I think Elm have similar rules, the official code format tool is very opinionated.
  - entropic 7y ago
    I can attest to that, elm-format is an excellent tool and it is great to have a standard code formatter, one less thing to worry or argue over when writing code!
- McWobbleston 7y ago
  F# doesn't allow tabs unless you use a compiler directive
- earenndil 7y ago
  Zig doesn't allow tabs in source code—which is a bit odd, since they don't have significant whitespace.
truth_seeker 7y ago
If PureScript is Haskell, TypeScript is ML Lately, TypeScript has become more scalable across existing npm libraries and also introduced new advanced types. It looks like Microsoft guys learned a lot from C# and F# type system and feedback from their users https://www.typescriptlang.org/docs/handbook/advanced-types.html https://www.typescriptlang.org/docs/handbook/advanced-types....
- wtetzner 7y ago
  > If PureScript is Haskell, TypeScript is ML If you want ML, why not OCaml with js_of_ocaml or BuckleScript?
- dwhitney 7y ago
  Once you get a taste for higher kinded types (aka: type constructors), there is no going back! PureScript is fantastic language with an active an open community. Best place to start (IMHO) is https://github.com/lumihq/purescript-react-basic https://github.com/lumihq/purescript-react-basic You can pretty quickly get a react app up and running
  - truth_seeker 7y ago
    Don't get me wrong. I love PureScript and HKT but the fact that it requires complete buyout to Purescript ecosystem overwhelms my team members and becomes a hard sell. To build a PS layer on top existing JS libraries isn't straight forward. Now that they introduced so many breaking changes, it will take time for other PS libraries to catch up. May be I might go back to PS when 1.0 release happens and I hope many things are stable including libraries which I need in day to day full stack development. Typescript in the last couple of years introduced a nice way to compose types and ways to get rid of many other common JS gotchas. They have type definitions for almost all the usable npm libraries, which helps you jump-start the development.
    - ff_ 7y ago
      It really didn't take long for libraries to catch up, we already released a Package Set compatible with 0.13, two days after the release. That's a set of the most used ~200 libraries in the ecosystem. https://github.com/purescript/package-sets/releases/tag/psc-0.13.0-20190531 https://github.com/purescript/package-sets/releases/tag/psc-...
asplake 7y ago
Syntax question, after looking at a couple of examples: Long wished more languages had a ‘where’ clause (suspect it could be really nice to have in Python), but why the ‘where’ at the end of the initial ‘module’ line? I guess it’s doing something consistent, but it does look a bit odd
- natefaubion 7y ago
  It's something that comes from Haskell. The `where` keyword always starts a new layout/indentation context. It's not strictly necessary and there are ways around it, so it's just a point of consistency.
jaequery 7y ago
what is scary about all these TypeScript, PureScript, Elm, etc, is that for variety of reasons, any one of these can just come and go. coffeescript anyone? i'd tread very carefully and wisely before choosing any one of these paths. it only makes sense imo if you come from Haskell, Clojure, or some other ML background to have an explicit interest in these languages.
- recursive 7y ago
  Typescript is essentially just javascript with types. The compiler just checks and then takes the types out. So with typescript, if you need to migrate away, you just take your compiler output, and ditch your .ts files. The output is generally just as readable as the input.
- iLemming 7y ago
  Coffeescript did not offer anything but different syntax. It hasn't improved the semantics of the language. Some people liked it and some didn't. Elm, PureScript, and Clojurescript are fundamentally different languages. Javascript today has bloated, and it keeps growing. Experienced developers tend to dislike it. Newbie developers struggle with it. It is no longer "a small language with a low entry barrier". ECMAScript specification is already bigger than Java's. PLs of today and the next couple of decades will be striving for optimizing for programmer's productivity, performance, or correctness of the program. Javascript today does not fit in any of these categories. So it is only natural - the trend of using alt-js langs will only grow.

90 points by valb 7y ago

I noticed a few languages removing support for octal and binary literals. I wonder why. I find them useful and the parser overhead seems minimal to keep them around.

wtetzner 7y ago
Yeah, it never made sense to me not to include those, given how simple it is.
- marquis-chacha 7y ago
  The typical octal literal syntax I've seen uses a 0 prefix. This gives rise to quite a few gotchas, as most people think of leading 0's as being non-value-changing. Maybe 0o12345670?
  - wtetzner 7y ago
    Yeah, I agree that it's not a good syntax. I do think 0o is a good prefix though.
ergothus 7y ago
Generally developers tend to either (1) misunderstand them when they encounter them in the wild or (2) accidentally invoke them. (I believe multiple languages have had issues with '04' being treated as an octal, which works fine and doesn't trigger developer notice until they encounter '09' in the wild). Whether these are VALID concerns I won't take a stance on - just saying these are the reasons I've seen cited.
- wtetzner 7y ago
  Why not use 0x,0b, and 0o for hex, binary, and octal literals? I never liked the fact that a number starting with 0 was treated as octal.
  - steinuil 7y ago
    OCaml does just that; it might have been the first language to have 0b and 0o prefixes for binary and octal literals. https://discuss.ocaml.org/t/the-origin-of-the-0b-01-notation/3180 https://discuss.ocaml.org/t/the-origin-of-the-0b-01-notation...
natefaubion 7y ago
We found no usages of it in the wild. If there is real-world need for them, we'll consider adding them back.
- scrollaway 7y ago
  FWIW I use binary literals a bunch in python, either when working with binary file formats or with bitfields.
  - natefaubion 7y ago
    Yes, I'm not saying there aren't usages for them in general, but PureScript currently occupies a niche that doesn't get down to the level of binary file formats. This change is more about "only supporting what we need to right now", rather than "we don't like binary literals". As noted elsewhere, it's not difficult to add support for them when we need to.

Scarbutt 7y ago

What happened to the original author of PS? https://github.com/purescript/purescript/graphs/contributors https://github.com/purescript/purescript/graphs/contributors

dwhitney 7y ago
Like many of us, he had children and couldn't keep up with the workload, so he took a step back. Fortunately there is a very active community working on PureScript!
gb 7y ago
Life! :) He still uses PS and chimes in on some issues, but doesn't really have time to work on the compiler anymore: https://twitter.com/paf31/status/941745900426215424 https://twitter.com/paf31/status/941745900426215424
kepano 7y ago
I don't speak for Phil, but I do work with him at Lumi where we use PureScript for almost all frontend. It's been really fun to show that PureScript can be used successfully in production. You can see some of our tutorials and open source projects here: https://www.lumi.dev https://www.lumi.dev

dmitryminkovsky 7y ago

Are there other languages that make an opinion on tabs/spaces? This seems nice. > The only whitespace now allowed in code is ASCII space and line endings. Since you must use indentation to format PureScript code (unlike Haskell), we felt it was best to be more restrictive in what you can write instead of allowing potentially confusing behavior (implicit tab-width, zero-width spaces, etc). You can still use unicode whitespace within string literals. I’m also wondering about the removed literals.

nathanyukai 7y ago
I think Elm have similar rules, the official code format tool is very opinionated.
- entropic 7y ago
  I can attest to that, elm-format is an excellent tool and it is great to have a standard code formatter, one less thing to worry or argue over when writing code!
McWobbleston 7y ago
F# doesn't allow tabs unless you use a compiler directive
earenndil 7y ago
Zig doesn't allow tabs in source code—which is a bit odd, since they don't have significant whitespace.

truth_seeker 7y ago

If PureScript is Haskell, TypeScript is ML Lately, TypeScript has become more scalable across existing npm libraries and also introduced new advanced types. It looks like Microsoft guys learned a lot from C# and F# type system and feedback from their users https://www.typescriptlang.org/docs/handbook/advanced-types.html https://www.typescriptlang.org/docs/handbook/advanced-types....

wtetzner 7y ago
> If PureScript is Haskell, TypeScript is ML If you want ML, why not OCaml with js_of_ocaml or BuckleScript?
dwhitney 7y ago
Once you get a taste for higher kinded types (aka: type constructors), there is no going back! PureScript is fantastic language with an active an open community. Best place to start (IMHO) is https://github.com/lumihq/purescript-react-basic https://github.com/lumihq/purescript-react-basic You can pretty quickly get a react app up and running
- truth_seeker 7y ago
  Don't get me wrong. I love PureScript and HKT but the fact that it requires complete buyout to Purescript ecosystem overwhelms my team members and becomes a hard sell. To build a PS layer on top existing JS libraries isn't straight forward. Now that they introduced so many breaking changes, it will take time for other PS libraries to catch up. May be I might go back to PS when 1.0 release happens and I hope many things are stable including libraries which I need in day to day full stack development. Typescript in the last couple of years introduced a nice way to compose types and ways to get rid of many other common JS gotchas. They have type definitions for almost all the usable npm libraries, which helps you jump-start the development.
  - ff_ 7y ago
    It really didn't take long for libraries to catch up, we already released a Package Set compatible with 0.13, two days after the release. That's a set of the most used ~200 libraries in the ecosystem. https://github.com/purescript/package-sets/releases/tag/psc-0.13.0-20190531 https://github.com/purescript/package-sets/releases/tag/psc-...

asplake 7y ago

Syntax question, after looking at a couple of examples: Long wished more languages had a ‘where’ clause (suspect it could be really nice to have in Python), but why the ‘where’ at the end of the initial ‘module’ line? I guess it’s doing something consistent, but it does look a bit odd

natefaubion 7y ago
It's something that comes from Haskell. The `where` keyword always starts a new layout/indentation context. It's not strictly necessary and there are ways around it, so it's just a point of consistency.

jaequery 7y ago

what is scary about all these TypeScript, PureScript, Elm, etc, is that for variety of reasons, any one of these can just come and go. coffeescript anyone? i'd tread very carefully and wisely before choosing any one of these paths. it only makes sense imo if you come from Haskell, Clojure, or some other ML background to have an explicit interest in these languages.

recursive 7y ago
Typescript is essentially just javascript with types. The compiler just checks and then takes the types out. So with typescript, if you need to migrate away, you just take your compiler output, and ditch your .ts files. The output is generally just as readable as the input.
iLemming 7y ago
Coffeescript did not offer anything but different syntax. It hasn't improved the semantics of the language. Some people liked it and some didn't. Elm, PureScript, and Clojurescript are fundamentally different languages. Javascript today has bloated, and it keeps growing. Experienced developers tend to dislike it. Newbie developers struggle with it. It is no longer "a small language with a low entry barrier". ECMAScript specification is already bigger than Java's. PLs of today and the next couple of decades will be striving for optimizing for programmer's productivity, performance, or correctness of the program. Javascript today does not fit in any of these categories. So it is only natural - the trend of using alt-js langs will only grow.