
TypeScript 2.4 RC - rpeden
https://blogs.msdn.microsoft.com/typescript/2017/06/12/announcing-typescript-2-4-rc/
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josteink
String Enums look nice. I'm also looking forward to the improved type-checking
for promises and callbacks.

All in all looks like a solid release, although breaking changes means I'll be
a little hesitant with updating anything critical :)

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cletusw
Of course, it looks like all of the breaking changes introduce compile time
errors, so if you try it out and it compiles, you're good!

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killin_dan
That's an incredibly smooth transition. Microsoft has really learned from the
javaverse's mistakes regarding compatibility.

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teebot
The await import to lazy load modules is quite impressive. TypeScript goes
more and more beyond the compile-to-js promise

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highpixels
Dynamic imports is standards-track JS :) [http://2ality.com/2017/01/import-
operator.html](http://2ality.com/2017/01/import-operator.html)

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avodonosov
It might be better to have runtime system load code dynamically when
necessary, without programmer to care about this, e.g. on first invocation,
maybe pre-loading it based on call statistics from previous app runs. People
implement this already (I tried this too -
[https://github.com/avodonosov/pocl](https://github.com/avodonosov/pocl))

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STRiDEX
I was wondering what the string enum example compiled into. Its this.

[https://gist.github.com/scttcper/7691497d4b8db9ad6e599aa2d34...](https://gist.github.com/scttcper/7691497d4b8db9ad6e599aa2d34fdada)

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FLGMwt
Seems reasonable

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cassowary
They've finally begun backtracking on function parameter bivariance.
[https://blogs.msdn.microsoft.com/typescript/2017/06/12/annou...](https://blogs.msdn.microsoft.com/typescript/2017/06/12/announcing-
typescript-2-4-rc/)

They still think they're right: "Our experience has been that users generally
don't run into issues with this all that much", but they've started to
"tighten[] things up and compare[] the parameters which are callbacks
specifically". I'm just so excited and annoyed that they've finally partially
admitted they're wrong. Double annoyed that we're still on TS 1.8 :(

I just don't understand function parameter bivariance. It's not just that it's
wrong (if it was just theoretical I wouldn't've noticed), it's that it keeps
letting bugs through. You simply can't refactor the code and then fix it till
there's no errors because you'll run out of errors before you run out of
things that need changing. Or adding features in React+Redux, can you get it
to help you? Nup. At least that's a specific point you can remember to check.

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severus
Typescript has pretty good support for react and redux.

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cletusw
Looking forward to the string enums! I've been using
[https://github.com/Microsoft/TypeScript/issues/3192#issuecom...](https://github.com/Microsoft/TypeScript/issues/3192#issuecomment-261720275)
but it'll be nice to have this built-in.

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NathanFlurry
The term "weak types" is incredibly confusing to developers who have used
languages that support weak references. I was excited for a second there
thinking that "weak types" meant TypeScript would generate code for using a
`WeakMap` in order to create weak references, but I guess not.

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pspeter3
Very excited for type safe dynamic imports. Should make type safe code
splitting with webpack a breeze.

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bauerd
Can someone compare Flow and TS? Last time I worked with Flow I had to
constantly restart the server to get fresh typechecks. Is that still the case?
Other pros and cons?

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josh64
[https://djcordhose.github.io/flow-vs-typescript/elm-flow-
typ...](https://djcordhose.github.io/flow-vs-typescript/elm-flow-
typescript.html#/) compares Flow TS and Elm :)

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zwily
That was great, thanks.

