Clojurians Log v2

Shouldn't Clojure have some reader macro to requiring-resolve symbols? That way we wouldn't have to use resolve-fns like in clojure.core.server for every function that might be invoked both from code and from clj -X:alias

Ah, they are read by edn, macro wouldn't work

Problem statement: clj -X:alias puts a requirement on entry-point functions to be able to accept only edn-read data, thus making their use both from code and from entry point clunky if they are designed to accept non-data as arguments.

What is "non-data" @vlaaad? I'm not sure that even makes sense...

And these are not "main" functions. -main accepts a sequence of strings. -X is for regular Clojure functions, which, last I checked, accept regular Clojure data... which is what you get from reading EDN... what am I missing?

I want to create a function for people to use both as main and from code

Why? What problem are you trying to solve with that?

You can already invoke -main functions via the -m argument to clojure.

-X is a way to invoke additional functions -- non-main functions.

-m lets you invoke -main functions with strings. -X lets you invoke non-main functions with data.

https://insideclojure.org/2020/07/28/clj-exec/#execution

Yeah, I've read it. Several times.

-X is entry point

it's a main

No. Not a "main".

a different kind of main

No.

okay, we have slightly different definitions of main

let's stick to entry point

-X lets you invoke any function -- even private ones -- with data.

both -X and main are entry points

No. You're wrong.

You think there's a problem here because you're starting from an incorrect set of assumptions.

why -X is not an entry point?

Alex's post literally says that...

"entry point" just means you can call any function. You're ascribing too much significance to that.

-main != "entry point" in this case.

Also bear in mind that -X allows you to call your -main function with strings from the command line (with appropriate quoting) -- this is a more general feature, based on Clojure-is-about-functions-and-data. -main is the old-school world of command-lines-are-strings thinking.

(it's 1 am here -- I'm off to bed!)

no, -X does not allow to call -main, because it will pass it a map, when -main expects a seq of strings

good night 🙂

Oh yeah... It's almost a superset. It's certainly a more general feature tho'...

And good night.

So you could call -main if you only want to pass a single string 🙂

Although I’m not surprised this works, I would expect it to be undefined behavior that we shouldn’t rely on :D

That is an interesting question -- is this defined/supported behavior. Hopefully @alexmiller can comment on that tomorrow.

Disagree on the top here -X should pass only 1 map to a function (that this works here is a bug)

It’s a bug -X should only invoke functions of 1 map

It’s not a superset of clojure.main

I suppose ":arg" is a more appropriate name, with there only being one

Well the idea is that it is a map of args

Kv args, not positional

Thanks for the clarification @alexmiller -- but if it's really "Kv args" as opposed to positional, shouldn't it be calling the function like (f :k 42 :foo "bar")? If you want to make it clear that it really is intended to pass a single argument :arg would make more sense than :args (I agree with @dominicm on that).

And given the intent is to call the function with just a single hash map, you probably want to enforce that before people start abusing it (exactly as I was doing, apparently, and in particular by using it to call -main with a single string argument)...

Oh, I will :)

And to @vlaaad: I was wrong and I apologize. We still disagree on "main function" as a definition I think but we agree on "entry point" and now it seems that they are disjoint features since you're not supposed to be able to use -X to call -main with a single string.

The other place, I can think of, where Clojure already uses :fn / :args is for function specs and :args there is explicitly a sequence of arguments (it catches beginners out that even for single-argument functions you need s/cat) -- so I really do think the singular :arg would be better here (or something more indicative of this being a single hash map argument). But I know we can often bikeshed on names so I'll leave it at that.

yeah, I am unswayed, not going to change

No problem! It's hard to admit mistakes — you are a good strong person :)

I didn't want to call -main from -X btw, just tried to come up with an api for my function that is accessible from both these entry points... And from code... All at the same time

Yeah, now Alex has clarified the intent of -X it's clear they are disjoint entry points which is both good and bad. I think it means you're stuck with your cli in 10 lines approach to -main to allow calling into a common function.

I'm currently at 5 lines already :rolling_on_the_floor_laughing:

Gave up to simplicity of just edn

At work we have a similar entry point -main in our <http://worldsingles.jobs|worldsingles.jobs> namespace: we pass in the fully-qualified name of a function to call and positional string arguments that are then packaged into a single hash map in -main which then calls the fq function. Although we parse the string arguments and use them are configuration to start a system Component usually, and those fq functions accept a system map -- they can't quite be called via -X at this point.

Deleting lines is always good 🙂