I am using Typescript to give VSCode some idea of what my Rhino JavaScript (Java JavaScript) is doing, I am not using Typescript sources, I am still using JavaScript files with checkJS turned on.
(I know it sounds terrible but I know the risk, all safety off)
I have several scripts executed in a sandbox with injected variables that includes the entire Java OpenJDK, I dont want to provide typedefs for this, but I do want to provide some hints, what can I do to make TS not care about 1000's of globally injected variables and objects.
Short of building Typedefs from Java (Done this it too 5 hours to build, its not going to work)
I want to do this:
java.io.readFile(); // < TS wont care about this
context.outcome; // hey TS there is this thing I have defined, its a boolean
(2).map(); // TS this isn't right!
Top comments (24)
I feel you hard on this. I come from a C# background in which everything is type-checked to an extent that you become far more comfortable with generics than you thought possible. At my current position, we exclusively use TypeScript. Some of our codebase is still ES6 and some JS libraries really just feel super awkward in TS.
I've learned to embrace it a little bit, I still try to minimize my use of declaring stuff any, but sometimes that or creating incredibly specific interfaces are the only way I know to make my code compile.
However, I've also been embracing discriminated unions as a solution to a lot of my issues. It isn't applicable to every situation, but I feel like it's a big level-up for my expressibility
Ah C# I plan to try this out one day, but as a close relative of TS In terms of parentage, I can see the appeal.
Most of the time TS works fine but there's always a... "Hang on I don't need to protect this bit, it's already safe" or you may need an any.
In the early days I used Typescript for everything but now I use of for stuff that will be maintained, preferring prototype work in JavaScript.
Anyway for this task I have turned on type checking in js and not wrote a single TS file, only including a tsconfig file, not standard stuff, the JavaScript is executed in a sandbox ran from the Java side and we are injecting variables into that context, the entire Java stdlib is just too much to write out by hand but I do want some of the good bits...
It's too complex I fear, I may try flowtype instead, see how that works
I feel like your best bet to "do it the rightish way" would be creating some sort of code generator which could either parse the Java stdlib, pull method signatures from library files, or maybe even read code-completion data from another IDE like Eclipse. But I can see that getting out of hand and becoming a thesis project really quickly, haha.
I have used Flow before, and there is definitely a lot less support in terms for editor/IDE extensions, and I had the impression that the project had lost a lot of steam.
Thanks for posting this adventure though, I always love reading the insightful questions you post!
Oh man the result of this was a 5 hour build job, even declaring all the globals as any from the Java stdlib was really slow for the language server and vscode to handle. Unserpising.. I think I will give up on this for now
Did you play with the compiler options: noEmit: true, incremental: true?
I never knew I will want TypeScript so much, until I need to maintain an undocumented 2 years old code where they use "any" anywhere
So we are not emitting because we are using JavaScript sources and the backend is just checking JS. Anyway this answer seems to lead to a different question that I'm not asking but thank you anyway
For global variables, I don't think there is an option other than providing Typescript definitions for every single global variable. As in, take the list of injected variables. Then, create a
java.d.tswith something along the lines ofSomething like modifying the global object doesn't quite cut it
sigh it's as I feared, I have kind of done both but taken to the absolute extreme, generating all of the definitions from jars... But it was too much for
A: My CPU, B: the language server.
It took 5 hours to compile using multithread techniques in node, 33000 classes. It turned into a funny novelty challenge, (I was quite happy to have created a reliable compiler actually, probably the most resilient thing I have ever made). So yeah, a good plan if the language server was damn fast, but it's not so that's scrapped. Maybe I could try flowtype if that's sstilla thing. Or I could give up 😅
why not use lilscript
Cool, but it's not quite what I'm looking for, I'm staying with a well known solution (because our new devolpers are more likely to know typescript)
True still a good option
What's that, can't see any Google results
github.com/afolabi-david/lilscript...
github.com/DevBash1/LilScriptJS
If you don’t want type safety, just use JavaScript?
All explained in the description
I have a javadoc doclet for creating typedefs from java in my graaljs project... you'll probably have to use
declareand/or cast to anyThat sounds most realistic 👍
Ummm Typescript can be functional, it's just JavaScript, most people do use it functionally... But that's nothing to do with type safety, there are plenty of typesafe functional languages, F# for example
Take a look at the
fp-tsecosystem. That's real functional programming, and that's one easy way you can write more type-safe code.But I'd didn't ask for functional code 🥴
You asked for more type-safe TypeScript, so my response is: look for more functional solutions and you'll get more type safety.
I asked for less typesafe, but still typescript, I want to make typescript not care about non declared globals as the description states.
This is for a very unusual edge-case