Python vs Swift | Prime Reacts

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[ciscoserrano]

More Swift videos are needed! To answer your question in the video. Yes, you can write Swift anywhere using whatever tool you like. Contrary to popular belief it’s not an Apple only language and you can use it anywhere from Windows to Linux to the web.

You can write in Vim and also use the LSP for some really nice language features. (:

[slippydouglas]

8:29 Swift collections are pass-by-copy, _but also_ Swift has good copy-on-write analysis by the compiler. So a pass-by-copy when the caller never uses that value again (only the callee uses it) is often a fast pass of ownership without the programmer having to annotate or do anything extra.

[kaljsdlksjfd]

Swift is the most ergonomic safe language in existance

[isodoubIet]

A typeclass in Haskell is not the same as a class. It's closer to Rust traits; a family of types for which certain functions are defined. The closest thing to a class in Haskell would be a Record (essentially a struct with godawful syntax).

[junebash]

Swift collection types (array, dictionary, set, string, etc) are copy on write, but this is not built into the language itself; they are implemented in the standard library that way. In essence, they are reference types under the hood, but before any mutation, the reference count is checked, and if there is more than one reference, it makes a new heap allocated copy before performing the mutation.

[austinsiu]

One thing I like about swift is how the language can constantly offer features to you that you need, but not flooding them all to you on day 3 of learning. On the other hand, if you suddenly need some advanced feature, it is difficult for you to know what are the prerequisites because it just suddenly feels like a foreign language

[MAH]

In case anyone wants to know the details of Swift's CoW, here's what I know:

Generally speaking, for any value type (any structs or enums), if you make an immutable copy of it, (like if you pass it as a param to a function, or do `let arr2 = arr1`), the compiler passes a reference to that instance. However, if you make a mutable copy, (`var arr3 = arr1`), the compiler makes a copy of it and send it. You can neither modify the value of an immutable value-type property nor mutate any of its members.

Swift's collections are value types, so they're passed by value, but they have copy-on-write semantics, and that's handled by the implementation.

So, if you make an immutable copy of an array, then you're sharing the reference to the instance itself. If you make a mutable copy, then a copy is made, which is, in reality, just the reference to the underlying storage. When you get to actually mutate the values within the array, a copy is made of the underlying storage, and then the copy gets the changes.

[burarum]

In deep learning context tensors are n dimensional arrays BUT what separates them (and what the degen twitch chat did not mention) from lets say vanilla Numpy arrays, if we are in python land, is that tensors have the additional machinery to be part of a computational graph and gradient computations in the graph using automatic differentiation that all deep learning libraries usually implement. For example in Pytorch all tensors have requires_grad attribute to imply if gradients should be calculated for said tensor.

[JohnR]

Would love to see more Swift content. It’s one of my favorite languages ❤

[tapashmajumder]

Swift is awesome! I wish you could use it for more things.

[martinvuyk]

When prime learns Mojo's language features... Imagine this same dude learnt all of the lessons fron building LLVM, Swift, Tensorflow XLA "generalization" (which became MLIR as far as I understand), and then went and built a programming language that mixes Rust, C++, and python concespts with a pragmatic take and letting the programmer decide how to use the features

[JorgetePanete]

Swift has UTF-8 checks for identical characters, I like that

[rickdg]

When you start searching for Swift, both the content creators and the tooling seemed to be focused on publishing to the App Store. There is movement on the server side, but it doesn’t bubble up to where people can feel it.

[slippydouglas]

10:53 _”I'm curious how you do like shared references, ones where 2 functions can mutate a value without copy on write.“_ A couple of options:
1. Pass by reference (&-prefix) to a function with an inout arg (like C# and many other languages).
2. Much more commonly, wrap your value type instance in an object type (a class, as opposed to a value primitive type or a struct or enum, like C++ and many other languages).
3. Use closures to get/set the original value. A bit esoteric, but sometimes this is the mechanism under custom type-erasing types or custom property wrappers attributes (again, drawing some similarities to C#).

[ruanpingshan]

Swift has the nicest closure syntax of any language I've used. Especially how it gives you implicitly defined parameters like $0, and $1, etc. Makes it really compact to just map to some property of the objects in the list.

[kosnowman]

I didn't realize the danger of passing an object as an argument is actually by passing the reference value (address/pointer) and any changes will mutate to the root of the object until 2 weeks ago at my college was talking about this in detail during the Java lecture.
Shamefully enough I was working as a JS dev full time and I didn't know that until now

[jeffrey]

It’s always real fun when data scientists create cool bugs when dealing with pandas dataframes, passing them around like everything is a copy. I was one of those data scientists once. Luckily I am naturally curious and also once dabbled a bit in C after which everything got a bit easier. But the minimum is to once read a blog entry on shallow and deep copies in python.

[sylarfx]

primeagean: ... right now swift has everything what I want ...
me: hmmm, where did I hear this before?

[bpo]

Totally doesn't matter but I really like in Swift being able to write a list of lets or vars without re-writing the let/var. It's silly but I miss it when I switch languages. I think the only other language compiled language I could do this in was Nim?

[gjermundification]

8:29 Swift makes a distinction between value types; struct and reference type; class. Basically you can do both heap and that other thing. Borrowing approaching recent releases of the language.