AstonJ

AstonJ

Do you say 'unpack' or 'destructure'?

Consider this Erlang code:

Rectangle = {rectangle, 20, 10}.
{rectangle, Width, Height} = Rectangle.
> Width.
20
> Height.
10

When I was watching an Elixir video the person kept calling this ‘destructuring’ (which I think is what they say in the JS world?) but Joe Armstrong, in his book Programming Erlang, calls this ‘unpacking’ - so I am curious, how do you refer to it when using a BEAM language?

  • Unpack
  • Destructure
  • Use the terms interchangeably depending on the language
  • Something else - please say in thread!

0 voters

Most Liked

chriseyre2000

chriseyre2000

Technically it’s pattern matching since we can be more specific by repeating a variable to ensure that it is used in multiple places.

Eiji

Eiji

Object : typeof instance === "object". Special non-data but Structural type for any constructed object instance also used as data structures: new Object, new Array, new Map, new Set, new WeakMap, new WeakSet, new Date and almost everything made with new keyword;

Source: JavaScript data types and data structures - JavaScript | MDN

This quote shows us that equivalent/similar data types across languages are implemented and therefore grouped differently which means that we can’t use exactly same naming. Different naming forces new developer to think: Why it's named like that? and that ends up with looking for it’s definition.

The destructuring assignment syntax is a JavaScript expression that makes it possible to unpack values from arrays, or properties from objects, into distinct variables.

Source: Destructuring assignment - JavaScript | MDN

Having in mind that both destructure and unpack are used only for arrays and objects it’s confusing to use them in Elixir for other data types like for example string. Destructure naming could also be confusing for newbies as we have structs.

Destructure and unpack antonyms suggest that we have something structured or packed which is not always true. While it’s common to say that we are unpacking bits from string still we can’t say that we are unpacking something from literal like for example: 5 = variable.

Generally i.e. for all data types I prefer to think about some connection of assignment, fetch, pattern and take words (which are most common) like taking by pattern or something like that.

@AstonJ Considering your Erlang code we can say that we are taking items: rectangle, Width and Height by 3-element tuple pattern of Rectangle variable. What do you think about it?

Where Next?

Popular Backend topics Top

AstonJ
Currently a hot topic in the BEAM world, let’s start a thread for it (as suggested by @crowdhailer here) :smiley: What are your current...
New
New
New
bot
So you want to live-reload Rust - fasterthanli.me. Good morning! It is still 2020, and the world is literally on fire , so I guess we c...
New
CommunityNews
The Magic of Python Context Managers. Recipes for using and creating awesome Python context managers, that will make your code more read...
New
AstonJ
If you are experiencing Rails console using 100% CPU on your dev machine, then updating your development and test gems might fix the issu...
New
Exadra37
Finishing my app to take notes on Videos: I am aiming to put it online on my playground by this weekend. Edit: It’s up https://video...
New
mafinar
So I was thinking of trying out Crystal, I had tried it multiple times but left it midway. Now that there’s a book on it and it’s version...
New
mafinar
I’ll be participating. This would be very interesting because I have been having coders block + a lot of distraction this weekend. But l...
New
jaeyson
Sorry for the very vague noob question, I really want to ask this: When do we use async or sync code in the context of Elixir? AFAIK gen...
New

Other popular topics Top

AstonJ
If it’s a mechanical keyboard, which switches do you have? Would you recommend it? Why? What will your next keyboard be? Pics always w...
New
brentjanderson
Bought the Moonlander mechanical keyboard. Cherry Brown MX switches. Arms and wrists have been hurting enough that it’s time I did someth...
New
New
PragmaticBookshelf
Rust is an exciting new programming language combining the power of C with memory safety, fearless concurrency, and productivity boosters...
New
PragmaticBookshelf
Learn different ways of writing concurrent code in Elixir and increase your application's performance, without sacrificing scalability or...
New
First poster: AstonJ
Jan | Rethink the Computer. Jan turns your computer into an AI machine by running LLMs locally on your computer. It’s a privacy-focus, l...
New
sir.laksmana_wenk
I’m able to do the “artistic” part of game-development; character designing/modeling, music, environment modeling, etc. However, I don’t...
New
PragmaticBookshelf
Explore the power of Ash Framework by modeling and building the domain for a real-world web application. Rebecca Le @sevenseacat and ...
New
PragmaticBookshelf
Fight complexity and reclaim the original spirit of agility by learning to simplify how you develop software. The result: a more humane a...
New
mindriot
Ok, well here are some thoughts and opinions on some of the ergonomic keyboards I have, I guess like mini review of each that I use enoug...
New