GeZe

FYI, it would not be accurate to say that "The Flow people moved on to ReScript".

Another example would be the difference between their enum features: https://medium.com/flow-type/typescript-enums-vs-flow-enums-... "TypeScript Enums vs. Flow Enums"

GeZe

5년 전discuss

Flow also supports "discriminated unions" [0], and did so before TypeScript (Flow's announcement in July 2015: https://flow.org/blog/2015/07/03/Disjoint-Unions/, TypeScript's announcement in August 2016: https://devblogs.microsoft.com/typescript/announcing-typescr...), though it doesn't yet support destructuring the "kind" field as was just added to TypeScript.

[0] https://flow.org/try/#0C4TwDgpgBAggxsAlgewHZQLwCgq6gHygG8oBr...

GeZe

5년 전discuss

Here are the docs for exporting/importing enums: https://flow.org/en/docs/enums/using-enums/#toc-exporting-en... - works fine with the new export/import syntax.

Docs for enums compilation/runtime are here: https://flow.org/en/docs/enums/defining-enums/#toc-enums-at-...

GeZe

10년 전discuss

You can similarly search/replace JS code, but using pattern matching and CSS style selectors instead of writing code, with Grasp. It's usable from the command line like sed.

http://www.graspjs.com/

For instance changing all calls to "calc" from taking two arguments to taking one object literal instead (eg. `calc(1, 2)` to `calc({from: 1, to: 2})`, is as easy as:

    $ grasp -r -e 'calc($a, $b)' -R 'calc({from: {{a}}, to: {{b}}})' file.js

(Where the two arguments to "calc" could be any arbitrary nested expressions, which could not be safely handled by a regular expression)

GeZe

12년 전discuss

For a tool dedicated to searching and replacing JS in this way (AST aware), check out http://graspjs.com

You can use both CSS style selectors, and pattern matching, to both search and replace your code.

GeZe

13년 전discuss

Self was one of the inspirations behind JavaScript, particularly its prototype system.

http://en.wikipedia.org/wiki/Self_(programming_language)

GeZe

13년 전discuss

Looks like someone has started one: https://github.com/joneshf/sublime-grasp

GeZe

13년 전discuss

Cool project! As monjaro mentions, the two examples are not equivalent however - the grasp example replaces every binary expression (alias: bi) with an addition operation with the right and left hand sides switched. This is a very trivial example, but hints at the great power available.

Grasp has two different query types, the default, squery - selector query, CSS style selectors, and equery (-e, --equery) - example query, JS code examples with wildcards.

In the grasp example above, we are using squery. jsgrep is similar to equery. You could do the following search in equery, and it would be more equivalent to the example you posted:

    f(__ < __, __ == __)

The only thing missing is the named wildcards for easy replace - that's a good idea and a feature to add to grasp 0.2.0!

You can check out the docs on squery (http://graspjs.com/docs/squery/) and equery (http://graspjs.com/docs/equery/)

GeZe

13년 전discuss

I plan to add support for both LiveScript and CoffeeScript to grasp in the future.

PS. If anyone has any questions about grasp please let me know!

GeZe

13년 전discuss

If you are looking for a syntax closer to Haskell's, you can take a look at LiveScript (http://livescript.net/)

eg.

    getUserFriends = (userName) ->
      user <- findUser userName
      friends <- findFriends user
      ...

Specifically, the section on "backcalls": http://livescript.net/#backcalls

GeZe

13년 전discuss

More specifically, this has to do with the Big Mac Index by The Economist.

http://en.wikipedia.org/wiki/Big_Mac_Index

http://www.economist.com/content/big-mac-index

GeZe

13년 전discuss

LiveScript allows partially applied operators, including property access. You can do:

    totals = map (.total), orders

http://livescript.net/

GeZe

13년 전discuss

For those who don't want to wait for the book, I've written a brief article covering some concepts of functional programming in JavaScript: http://livescript.net/blog/functional-programming-in-javascr...

It covers first class and higher order functions, currying, partial application, composing functions, using operators as functions, comprehensions, and immutability.

GeZe

13년 전discuss

This syntax already exists in LiveScript (http://livescript.net/#backcalls) which compiles to straightforward JS.

    a <- doFirstThing()
    b, c <- doSecondThing(a)
    doFinalThing(b + c)

GeZe

13년 전discuss

The name is a joke, the project is not. "LiveScript was one of the original names for JavaScript, so it seemed fitting. It's an inside joke for those who know JavaScript well." (from the site)

LiveScript hasn't been used as a name for JavaScript in almost two decades.

GeZe

14년 전discuss

Try learning Haskell. The concepts I discovered while learning it were very influential in my approach to other languages, even if I don't use Haskell itself all the time.

I would suggest http://learnyouahaskell.com/

GeZe

14년 전discuss

LiveScript compiles almost 1 to 1 to JavaScript and has no runtime, making it easier to debug and comprehend for JavaScript programmers. You can access and use any JavaScript library without having to resort to a special syntax. For JavaScript programmers, it may be easier to use LiveScript. For Haskell programmers, it may be easier to use Fay.

I think many JavaScript programmers are looking for JavaScript (CoffeeScript) + functional programming rather than something purely functional as it allows them to use all that they've learned and mastered from JavaScript (often in an enhanced way) while using functional concepts as they learn them.

GeZe

14년 전discuss

For those interested in functional programming, but with a desire for something a bit more pragmatic (and highly compatabile with CoffeeScript), you can check out LiveScript http://livescript.net

Functional Programming in JavaScript using LiveScript and prelude.ls: http://livescript.net/blog/functional-programming-in-javascr...

GeZe

14년 전discuss

60 character solution in LiveScript[0], without using 'if's, also easily extensible!

[1 to 100]map(->[s for s,n of{Fizz:3,Buzz:5}|it%n<1]*''||it)

[0]http://gkz.github.com/LiveScript/

Submissions

TypeScript Enums vs. Flow Enums

Scaling Flow to tens of millions of lines of JavaScript with Types-First mode

Refactoring your JavaScript code with Grasp

Functional Programming in JavaScript using LiveScript - Part 2

The CoffeeScript of your dreams: LiveScript

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