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Elixir for Humans Who Know Python

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Re: Elixir for Humans Who Know Python

#81

Post by freedomben »

marhee wrote: post #50
josevalim wrote: post #37

Earlier quoted context omitted.

I would find such principled approach to be unproductive. The same could be said about Python, the `.` is equally syntax sugar for passing the object as first argument. So if we take this Pandas code: df.sort_values('dep_date') .groupby('name')['duration'] .transform('cumsum') If we were to pass df as first argument in nested calls, I would find it less readable. But I would also find using variables in this case to…

You could reuse df (as the method presumably change df), in addition: - you have more room to comment what the intention of the code/call is - you have room to handle / check for errors For example, the "sort_values" and "groupby" in you example are obvious most readers. But "transform("cumsum") is probably obvious to you but I don't know the intention of the code. By reassigning to df it makes it clear that the retu…

> You could reuse df (as the method presumably change df),

Then what's the point in assigning to intermittent variables (as your criticism about the pipe was)? You don't get any added clarity about the intermittent intentions that way...

Re: Elixir for Humans Who Know Python

#82

Post by Alir3z4 »

traverseda wrote: post #76
josevalim wrote: post #70

Earlier quoted context omitted.

Thanks for the insights, I appreciate it! I will take some time to go through the docs and learn more. One last question for now (I hope): after the migrations are auto-generated, do you check them into version control? > Models are for developers and generally developers have all the permissions any way To clarify, the reason why you would want to have read-only models is rather in complex data model cases or for pe…

Yep, you do check the migrations into version control. >For example, if you have a large model with 50 fields, defining a subset with 10 fields can be beneficial to performance in several queries. Other than that, I agree with you. Nope, the django ORM has several helpers here. What you do in the most basic case is do something like MyTable.objects.filter(key__gte=12).only("field1","field2","field3") Which will (duri…

> For a long time I didn't realize why people were so down on ORMs until I tried using a non-django ORM, it really does set the bar.

This. Very much this.

I have given up on one finding such. The closest and nicest one that comes to mind is SQLAlchemy. The rest of languages or frameworks have indeed nothing compared to Django ORM and SQLAlchemy. It's not even fair to compare them.

Re: Elixir for Humans Who Know Python

#83

Post by submeta »

pg_1234 wrote: post #80
submeta wrote: post #77

I love functional programming because it feels natural to me to have functions that always return a value (method chaining or postfix notation FTW!) do not mutate data (and therefore avoid side effects), and use clear naming conventions for any potentially destructive functions. However, Python's popularity, vast library, and strong community make it a more practical choice for solving problems - at least when progra…

As a Python programmer, I truly believe Elixir/Phoenix is the best stack out there from a technical perspective. However the incredible breadth of libs and resources ... and most importantly the mind share (both available devs, but more importantly available jobs for seniors who commit to Elixir) means that it is still just not a competitive choice. Almost all commercial software dev is not about technical excellence…

> Almost all commercial software dev is not about technical excellence, but rather about applying the available tech to a particular business domain

A manager focused on results will not make decisions based on beauty or excellence, unfortunately, but based on other criteria: What gets the job done, availability of resources, price. That’s why PHP is still the most used programming language in web dev in Germany (instead of Ruby/Rails or Python/Django), and Excel is the most used tool for data analysis in the business world (instead of Python + Pandas).

Re: Elixir for Humans Who Know Python

#84

Post by josevalim »

traverseda wrote: post #76
josevalim wrote: post #70

Earlier quoted context omitted.

Thanks for the insights, I appreciate it! I will take some time to go through the docs and learn more. One last question for now (I hope): after the migrations are auto-generated, do you check them into version control? > Models are for developers and generally developers have all the permissions any way To clarify, the reason why you would want to have read-only models is rather in complex data model cases or for pe…

Yep, you do check the migrations into version control. >For example, if you have a large model with 50 fields, defining a subset with 10 fields can be beneficial to performance in several queries. Other than that, I agree with you. Nope, the django ORM has several helpers here. What you do in the most basic case is do something like MyTable.objects.filter(key__gte=12).only("field1","field2","field3") Which will (duri…

Ack on migrations, tks!

---

For completeness, you can do the same in Ecto:

    from t in MyTable, where: t.key >= 12, select: ["field1", "field2", "field3"]
However, that will still allocate a "MyTable" struct in Ecto. And if that struct is large (say 50 fields), slots for it are allocated (but none of the actual data on the fields).

I am not familiar with Python Object Model enough but, if your Python example still allocates an object with slots for all 47 other fields besides the three selected, then you may still find yourself under circumstances you would rather have a "slim" version of the model and reduce memory allocation. This may be needed when you need to load dozens of thousands of entries into memory for processing or similar.

I am not saying this is a must have but I am just trying to clarify what my initial comment was about. :)

Re: Elixir for Humans Who Know Python

#85

Post by nickjj »

AlchemistCamp wrote: post #33
josevalim wrote: post #27

Earlier quoted context omitted.

> Django does not generate anything through scaffolding like Phoenix I was one of the co-authors of Devise, which is an integrated authentication solution for Rails (similar in spirit to Django), and you will easily find people who swear that the code generation solutions are miles better. That’s because eventually they’d want to customize how the framework or library work and then, instead of simply being able to ch…

Is there a channel where we can share suggestions for the upgrade guide? I think it would save people some time if the phx 1.6 -> phx 1.7 upgrade instructions started with the following two steps: 1.) Upgrade LiveView to 0.18.x (with link to https://hexdocs.pm/phoenix_live_view/changelog.html#0-18-0-2... ) 2.) Update web.ex macros for Phoenix Component (with link to https://hexdocs.pm/phoenix_view/Phoenix.View.html#m…

I updated my example Docker / Phoenix app from 1.6 to 1.7 this morning.

I put it all into 1 commit: https://github.com/nickjj/docker-phoenix-example/commit/3733...

There were a number of things not covered in the upgrade guide. Lots of small changes between what the new app generator provides, csrf tokens being set in a different way, etc..

Re: Elixir for Humans Who Know Python

#86

Post by dasil003 »

spapas82 wrote: post #60
josevalim wrote: post #27

Earlier quoted context omitted.

> Django does not generate anything through scaffolding like Phoenix I was one of the co-authors of Devise, which is an integrated authentication solution for Rails (similar in spirit to Django), and you will easily find people who swear that the code generation solutions are miles better. That’s because eventually they’d want to customize how the framework or library work and then, instead of simply being able to ch…

> instead of simply being able to change the code, you need to find the exact hook or configuration to get the behavior you want. I don't think that this is a bad thing. This is the purpose of a framework. To extend its functionality. If I wanted to re-write everything (or change the generated scaffolds) then I'd skip the framework and use libraries directly. I'd like to point out the biggest problem with scaffolding…

If your argument is that a configurable framework is easier than code gen for beginners, I agree. But that said, you don’t seem to be acknowledging the fundamental tradeoff which cuts both ways. Ultimately it depends on how close you want to stay to the paved path. I’ve built enough web products at this point that I’d rather have auth primitives than a configurable framework as the latter will be way more complicated than necessary to meet my needs.

For me it comes down to keeping business logic out of my framework. The logical extension of the framework + hooks model can be seen in something like Drupal. You can get amazing volumes of functionality launched quickly, but the UX is ERP-like in its rigidity. Obviously Django is not like this in the large, and the auth/admin stuff are much higher power-to-weight ratio than anything in Drupal, but it’s an interesting case study in looking at the implications of drawing different logical boundaries between framework and application.

Re: Elixir for Humans Who Know Python

#87

Post by pg_1234 »

josevalim wrote: post #45
ralmidani wrote: post #31

My perhaps slightly biased input on Python vs. Elixir (I worked with Python for different projects for a couple years, and have been using Elixir full-time for ~1.5 years). Elixir as a core technology for application development (as opposed to data science/ML/AI - it’s still early days for Nx/Axon/etc.) is better than Python in just about every way that matters; e.g. immutability by default eliminating whole classes…

If you don’t mind, I have some questions as I would like to learn more. Are you aware of a large models.py for reference and learning purposes? Is it expected to define the schema of all my models in a single place but none of the logic? Also, don’t you run into scenarios in Django where the automatic migration is not enough and you need to provide custom commands? In such cases, how do you provide them? And can you…

I don't think this is something that will come down to technical merits.

Unfortunately it is a popularity contest, where entrenched network effects are working against Elixir.

As a Python programmer, I truly believe Elixir/Phoenix is the best stack out there from a technical perspective.

However the incredible breadth of libs and resources ... and most importantly the mind share (both available devs, but more importantly available jobs for seniors who commit to Elixir) means that it is still just not a competitive choice.

Almost all commercial software dev is not about technical excellence, but rather about applying the available tech to a particular business domain. And there Python (and .Net, Java, PHP, Ruby ... even Go) are so far ahead that sadly Elixir doesn't look like it will make it.

I don't know that anything can be done about this. For all that I think Elixir is better, I, like most devs, am not about to sacrifice (or even impair) my career for the cause. Personal remuneration wins out.

Re: Elixir for Humans Who Know Python

#88

Post by ch4s3 »

noloblo wrote: post #44
michaelteter wrote: post #5

No offense to TFA author, but I don't think this is doing to sell Elixir to Python people. In fact, I have serious doubts as to whether most Python lovers would be willing to set aside their beliefs and practices to learn the Elixir way. Perhaps Phoenix and LiveView will be the gateway drug, but even to reach that point requires a lot of effort to understand functional programming and Elixir. Python has some function…

I think this article does capture the magic of elixir phoenix live view that is impossible in the async await madness hell in python. I cannot wait to try elixir Phoenix live view, elixir |> pipes, :atom pattern matching and ets pids to send and manage processes across servers none of these AFAIK are currently possible with the GIL and single threaded nature of python As the venerable prof Joe armstrong would say you…

You can pattern match on basically any shape, not just atoms. Imagine you’re parsing a protocol over tcp and want to grab groups of characters between deliverers, you can pattern match that. I rewrote an hl7 parser from Java to Ruby to Elixr some years ago and the elixir implementation performed as well as Java and was more readable by miles.

Re: Elixir for Humans Who Know Python

#89

Post by JPKab »

michaelteter wrote: post #5

No offense to TFA author, but I don't think this is doing to sell Elixir to Python people. In fact, I have serious doubts as to whether most Python lovers would be willing to set aside their beliefs and practices to learn the Elixir way. Perhaps Phoenix and LiveView will be the gateway drug, but even to reach that point requires a lot of effort to understand functional programming and Elixir. Python has some function…

"Python has some functional capabilities, but in my experiences with Python devs, those are little used and even shunned. Imperative, mutating loops are the Python way; and to suggest otherwise is to hear "But why would I need that? This (long functions with mutations everywhere and loops) is fine.""

Thank God I'm not stuck with low talent clowns like that.

Writing highly functional python isn't hard anymore, especially making use of mypy strong types, data classes, generator expressions/etc.

Using dict unpacking combined with things like list comps is a really simple way to get trad Python devs getting more functional. My team is a bunch of experienced Python devs who happen to live Haskell/Clojure/etc so I guess that makes things easier.

Re: Elixir for Humans Who Know Python

#90

Post by Spivak »

Assuming the author is in the comments, the paragraph about data immutability is wrong. Integers are immutable in Python, when you created the lambda the name x is in its closure. When you assign to it it changes where the name is pointing to. Elixir does something wild and completely different. When you assign x that second time at that moment is creates a new variable behind the scenes and you transparently start using that one when you now refer to x in that scope. So lambda has a reference to x@0 and your outer scope has a reference to x@1.
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