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In my entire life as a programmer, this is the one thing that I've found most confusing. Our old codebase used a lot of curried Ramda functions and nobody on th

In my entire life as a programmer, this is the one thing that I've found most confusing. Our old codebase used a lot of curried Ramda functions and nobody on the team could read any of it. We spent a week ripping every single instance of it out and replaced it with regular lodash and never looked back and never had an issue with it again. After like ten or fifteen hours of trying to understand what currying is, I still have no idea, and frankly don't care. If I see it in a codebase it'd just be a big red flag to avoid that job altogether.

auggierose 3y ago
Ramda, lodash, no idea what currying is, ... Software is in good hands.
- solardev 3y ago
  Heh, so much of the world runs on basic business software. If it ran fine after the rewrite, with much less cognitive load, why not? These were just bog standard web pages that someone overengineered the hell out of, to a point that nobody else could understand or maintain it. Sure, that might win them l33t points, but wasn't very useful otherwise.
  - yakshaving_jgt 3y ago
    As a Haskell programmer, I have to agree with you. When you're writing Haskell, you should write idiomatic Haskell. Currying is part of that. It's a trivial concept and we use it liberally at work. If you're writing JavaScript though, I think it's a different story. I don't think JavaScript lends itself to FP in the way that Haskell or Elm does, and trying to make it do that only makes a project harder to work on.
- worddepress 3y ago
  Almost as if an astronaut can come, do their thing in a whirlwind and leave for another company 2 years later, while the remaining plebs have to figure it all out.
  - solardev 3y ago
    Yeah, a lot of the codebase was like that. Some lone wolf mad genius that occasionally left pieces of pure brilliance behind, but more often than not, just wrote code that was incredibly idiosyncratic and unnecessarily reinvented. Like he'd spend several files making a color gradient visualization system with his own scales, with an enthusiastic but limited understanding of color theory, that ended up producing mostly reasonable but occasionally insane color scales. We spent several days of back and forth discussions with him before understanding what he was actually trying to do (which isn't what his code was actually doing) and then replaced it with a one liner out of a standard visualization/color lib. The entire codebase was like that. It stood out to me as the work of someone who was very smart but worked alone and never had to work with a team, and never considered what someone trying to retrace his mental process would have to go through. He left zero documentation or comments, built the whole thing in a rush, sold it to another company, and we were the ones hired later to clean up his mess. Some of it was very good. He was really good at efficiently encoding low level network traffic over packet encodings he invented or heavily modified. Seemed like he would've been a brilliant signals engineer or cryptologist. But having to work with his ordinary business logic code was pretty nightmarish, if interesting from a reverse engineering and psychology point of view. It's just not how I would ever want to write code meant for mere mortals. But then again, he's a multi millionaire now and I'm a rando nobody living paycheck to paycheck, so I'm in no place to judge lol.
    - MarkSweep 3y ago
      > But then again, he's a multi millionaire now and I'm a rando nobody living paycheck to paycheck, so I'm in no place to judge lol. If he had not made such a big mess, you might not be getting this paycheck to clean it up. I think they call this “creating scope for other people” at big companies, real staff engineer stuff. =)
      - solardev 3y ago
        Heh, exactly. Some of us are just software janitors for the bigwigs.
bPspGiJT8Y 3y ago
> After like ten or fifteen hours of trying to understand what currying is, I still have no idea Maybe you could recall which learning materials you used?
- solardev 3y ago
  The Ramda docs, primarily, and Google searches. It just seemed like a lot of unnecessary complexity. We modified the parts we understood (or believed we did), and just rewrote the rest from scratch. The tests still passed, nobody else complained, the managers and customers never noticed, the devs were much happier, QA never said a word, and a whole class of bugs disappeared once we were able to reliably predict the output of simple helper functions. Shrug. Seemed like a win win. Probably the best thing we ever did to that codebase.
worddepress 3y ago
In Haskell it is easy. If you "forget" the last argument to a function, you get returned a function where you can provide that later on. A bit like saying "you can fill this in later". That is a "curried" function. Example add 1 2 // add is curried, you can use it like this, the "normal" way, returns 3 p = add 1 // since add is curried I can also provide just the first argument p 2 // and then apply the last argument to the intermediate results, returns 3 What is the point of using curried functions in JS? I am not really sure. It is not very ergonomic and I wouldn't like to use them in general. Maybe for some specific things it could be useful. In Haskell curried form is the default and the syntax and semantics really suits it. In JS non-curried is the default and it just looks odd, and you need libraries to support it. That library you mentioned doesn't look nice to use.
- zarzavat 3y ago
  It’s worth noting that even in Haskell, overuse of the so called point-free style is disliked for much the same reasons: https://wiki.haskell.org/Pointfree https://wiki.haskell.org/Pointfree There is a sliding scale and even at the Haskellers have a limit of how much point-free they can take. In JavaScript use of the style is problematic in another way: unlike Haskell in JS the length of the argument list is variable, which means that if someone adds another argument to either the caller or callee it can break the code in subtle and unexpected ways. For this reason it’s good practice to always wrap functions being passed as arguments to another function in a lambda expression. i.e instead of writing: g(f), you should usually write: g(x => f(x)) unless you have good reason to believe that g(f) is safe. This makes it difficult to use point-free style at all in JS. For example arr.map(f) is generally unsafe in JS because if `f` adds an extra default argument of type number then your code will break and even TypeScript won’t let you know.
  - epolanski 3y ago
    All your JS/TS example says is that the `f` callback is not curried, so your point is entirely lost on me.
- taneq 3y ago
  Honestly, a lot of these 'advanced' features aren't a good choice in most codebases IMO. The vast majority of 'enterprise' coding is CRUD and glue, where execution speed doesn't matter and being as simple and explicit as possible is the highest virtue. And the significant number of professional coders who worked hard to get their heads around things like pointers and printf format specifiers are still plenty productive in those kinds of codebases. Things like currying are fun but like anything that encourages gratuitously deep call trees, they wreck your locality of reference (as a developer) and force you to 'decompile' the code in your head in order to understand it. I'm sure that a top level developer would be able to write curried JS in such a way that it was clear and readable to another top level developer, but that's not the point. The code's not for you, it's for newbie who gets stuck with it when you move on.
082349872349872 3y ago
Function arguments work like the power rule for exponents in elementary school math: f a b = g(a,b) = f' b a (x^2)^3 = x^(2*3) = (x^3)^2
- solardev 3y ago
  You must've gone to a pretty kick ass elementary school. In mine, we'd play Connect Four and make paintings out of fake hieroglyphs...
  - 082349872349872 3y ago
    I'm fortunate my parents didn't stick with free-to-play, but were willing to spend 5-6 digits more to buy a house in the "good" school district: https://news.ycombinator.com/item?id=39946026 https://news.ycombinator.com/item?id=39946026
    - dxdm 3y ago
      Willing _and_ able.
      - aebtebeten 3y ago
        I grew up during the Cold War, so I don't know what the Young Pioneers were learning*, but we were good little capitalists, and we learned the Golden Rule: "Whoever has the gold makes the rules" (*maybe the ones who spent their summers at Artek were learning "whoever makes the rules has the gold"?)
  - inopinatus 3y ago
    When I were a lad, elementary school meant four hours of beatings in a muddy field, and we were glad of it
    - 082349872349872 3y ago
      On that note, I found Orwell's posthumously-published Such, Such Were the Joys (about his boarding school days) suggests the inspirations behind large swaths of 1984.
akdor1154 3y ago
Was the codebase in strict Typescript? I find currying to be sometimes useful in the right language / paradigm, as long as you can rely on the compiler to yell at you until you get it right. Dynamically typed functional retrofit on with no type checking though? Hell no, that's a write-once read-never mess of unmaintainable shite. (I also have been on a team with The Guy Who Wanted To Ramda, and I'm someone who writes build scripts in ocaml)
- solardev 3y ago
  It was a mishmash. The parts written by later employees were strongly typed and easy to follow. The parts he wrote weren't typed at all and frequently relied on implicit conversions and bitwise operators to do magic operations that would take us mere mortals several days to even begin to understand, all just to save what would've been like 3 lines of code and a single comment. Inheriting that codebase felt like watching one of those serial killer dramas... obviously a really smart guy, but with a psychology unlike most people I've ever met, and really hard to follow as a normal person. I still see him with a mixture of respect, awe, curiosity, and wonder. The thing is, none of the stuff he gave is was actually complicated. It's just a basic business dashboard. But he reinvented almost every single part of it in totally nonstandard ways that the whole project was less about coding and more about anthropology and forensic psychology.
  - HlessClaudesman 3y ago
    CSI: Code Shite Investigation
kccqzy 3y ago
> After like ten or fifteen hours of trying to understand what currying is I have doubts on whether this is a sincere attempt at understanding the concept. The linked wiki page is like a five minute read and that's enough to understand the concept at a user's level. What I suspect is that something else is tripping you up and causing code readability issues; but since you didn't know what currying is you incorrectly ascribed currying as the problem.
- threatofrain 3y ago
  Yeah 10-15 hours is kinda crazy for an introductory topic.
deleted 3y ago
[deleted]
curry_is_easy 3y ago
Since you know JavaScript, this should help. Uncurried: ((x, y) => x * y)(3, 5) === 15 Curried: (x => y => x * y)(3)(5) === 15 If you don't understand that, your problem is that you don't understand anonymous functions (lambdas), not that you don't understand currying.
fxj 3y ago
In my experience, functional programming really shines in rapid prototyping. However, in production code I would try to avoid it, because it can confuse developers that are not used to it and also sometimes I struggle myself when decoding the short "clever" one-liner that I wrote 5 years ago. But if you want to write very powerful code withing a single line it is really great and makes you very productive for finding solutions fast. It is a bit like the Perl throw-away code we were writing in the 1990s. ;-) just my 2 ct

auggierose 3y ago

Ramda, lodash, no idea what currying is, ... Software is in good hands.

solardev 3y ago
Heh, so much of the world runs on basic business software. If it ran fine after the rewrite, with much less cognitive load, why not? These were just bog standard web pages that someone overengineered the hell out of, to a point that nobody else could understand or maintain it. Sure, that might win them l33t points, but wasn't very useful otherwise.
- yakshaving_jgt 3y ago
  As a Haskell programmer, I have to agree with you. When you're writing Haskell, you should write idiomatic Haskell. Currying is part of that. It's a trivial concept and we use it liberally at work. If you're writing JavaScript though, I think it's a different story. I don't think JavaScript lends itself to FP in the way that Haskell or Elm does, and trying to make it do that only makes a project harder to work on.
worddepress 3y ago
Almost as if an astronaut can come, do their thing in a whirlwind and leave for another company 2 years later, while the remaining plebs have to figure it all out.
- solardev 3y ago
  Yeah, a lot of the codebase was like that. Some lone wolf mad genius that occasionally left pieces of pure brilliance behind, but more often than not, just wrote code that was incredibly idiosyncratic and unnecessarily reinvented. Like he'd spend several files making a color gradient visualization system with his own scales, with an enthusiastic but limited understanding of color theory, that ended up producing mostly reasonable but occasionally insane color scales. We spent several days of back and forth discussions with him before understanding what he was actually trying to do (which isn't what his code was actually doing) and then replaced it with a one liner out of a standard visualization/color lib. The entire codebase was like that. It stood out to me as the work of someone who was very smart but worked alone and never had to work with a team, and never considered what someone trying to retrace his mental process would have to go through. He left zero documentation or comments, built the whole thing in a rush, sold it to another company, and we were the ones hired later to clean up his mess. Some of it was very good. He was really good at efficiently encoding low level network traffic over packet encodings he invented or heavily modified. Seemed like he would've been a brilliant signals engineer or cryptologist. But having to work with his ordinary business logic code was pretty nightmarish, if interesting from a reverse engineering and psychology point of view. It's just not how I would ever want to write code meant for mere mortals. But then again, he's a multi millionaire now and I'm a rando nobody living paycheck to paycheck, so I'm in no place to judge lol.
  - MarkSweep 3y ago
    > But then again, he's a multi millionaire now and I'm a rando nobody living paycheck to paycheck, so I'm in no place to judge lol. If he had not made such a big mess, you might not be getting this paycheck to clean it up. I think they call this “creating scope for other people” at big companies, real staff engineer stuff. =)
    - solardev 3y ago
      Heh, exactly. Some of us are just software janitors for the bigwigs.

bPspGiJT8Y 3y ago

> After like ten or fifteen hours of trying to understand what currying is, I still have no idea Maybe you could recall which learning materials you used?

solardev 3y ago
The Ramda docs, primarily, and Google searches. It just seemed like a lot of unnecessary complexity. We modified the parts we understood (or believed we did), and just rewrote the rest from scratch. The tests still passed, nobody else complained, the managers and customers never noticed, the devs were much happier, QA never said a word, and a whole class of bugs disappeared once we were able to reliably predict the output of simple helper functions. Shrug. Seemed like a win win. Probably the best thing we ever did to that codebase.

worddepress 3y ago

In Haskell it is easy. If you "forget" the last argument to a function, you get returned a function where you can provide that later on. A bit like saying "you can fill this in later". That is a "curried" function. Example add 1 2 // add is curried, you can use it like this, the "normal" way, returns 3 p = add 1 // since add is curried I can also provide just the first argument p 2 // and then apply the last argument to the intermediate results, returns 3 What is the point of using curried functions in JS? I am not really sure. It is not very ergonomic and I wouldn't like to use them in general. Maybe for some specific things it could be useful. In Haskell curried form is the default and the syntax and semantics really suits it. In JS non-curried is the default and it just looks odd, and you need libraries to support it. That library you mentioned doesn't look nice to use.

zarzavat 3y ago
It’s worth noting that even in Haskell, overuse of the so called point-free style is disliked for much the same reasons: https://wiki.haskell.org/Pointfree https://wiki.haskell.org/Pointfree There is a sliding scale and even at the Haskellers have a limit of how much point-free they can take. In JavaScript use of the style is problematic in another way: unlike Haskell in JS the length of the argument list is variable, which means that if someone adds another argument to either the caller or callee it can break the code in subtle and unexpected ways. For this reason it’s good practice to always wrap functions being passed as arguments to another function in a lambda expression. i.e instead of writing: g(f), you should usually write: g(x => f(x)) unless you have good reason to believe that g(f) is safe. This makes it difficult to use point-free style at all in JS. For example arr.map(f) is generally unsafe in JS because if `f` adds an extra default argument of type number then your code will break and even TypeScript won’t let you know.
- epolanski 3y ago
  All your JS/TS example says is that the `f` callback is not curried, so your point is entirely lost on me.
taneq 3y ago
Honestly, a lot of these 'advanced' features aren't a good choice in most codebases IMO. The vast majority of 'enterprise' coding is CRUD and glue, where execution speed doesn't matter and being as simple and explicit as possible is the highest virtue. And the significant number of professional coders who worked hard to get their heads around things like pointers and printf format specifiers are still plenty productive in those kinds of codebases. Things like currying are fun but like anything that encourages gratuitously deep call trees, they wreck your locality of reference (as a developer) and force you to 'decompile' the code in your head in order to understand it. I'm sure that a top level developer would be able to write curried JS in such a way that it was clear and readable to another top level developer, but that's not the point. The code's not for you, it's for newbie who gets stuck with it when you move on.

082349872349872 3y ago

Function arguments work like the power rule for exponents in elementary school math: f a b = g(a,b) = f' b a (x^2)^3 = x^(2*3) = (x^3)^2

solardev 3y ago
You must've gone to a pretty kick ass elementary school. In mine, we'd play Connect Four and make paintings out of fake hieroglyphs...
- 082349872349872 3y ago
  I'm fortunate my parents didn't stick with free-to-play, but were willing to spend 5-6 digits more to buy a house in the "good" school district: https://news.ycombinator.com/item?id=39946026 https://news.ycombinator.com/item?id=39946026
  - dxdm 3y ago
    Willing _and_ able.
    - aebtebeten 3y ago
      I grew up during the Cold War, so I don't know what the Young Pioneers were learning*, but we were good little capitalists, and we learned the Golden Rule: "Whoever has the gold makes the rules" (*maybe the ones who spent their summers at Artek were learning "whoever makes the rules has the gold"?)
- inopinatus 3y ago
  When I were a lad, elementary school meant four hours of beatings in a muddy field, and we were glad of it
  - 082349872349872 3y ago
    On that note, I found Orwell's posthumously-published Such, Such Were the Joys (about his boarding school days) suggests the inspirations behind large swaths of 1984.

akdor1154 3y ago

Was the codebase in strict Typescript? I find currying to be sometimes useful in the right language / paradigm, as long as you can rely on the compiler to yell at you until you get it right. Dynamically typed functional retrofit on with no type checking though? Hell no, that's a write-once read-never mess of unmaintainable shite. (I also have been on a team with The Guy Who Wanted To Ramda, and I'm someone who writes build scripts in ocaml)

solardev 3y ago
It was a mishmash. The parts written by later employees were strongly typed and easy to follow. The parts he wrote weren't typed at all and frequently relied on implicit conversions and bitwise operators to do magic operations that would take us mere mortals several days to even begin to understand, all just to save what would've been like 3 lines of code and a single comment. Inheriting that codebase felt like watching one of those serial killer dramas... obviously a really smart guy, but with a psychology unlike most people I've ever met, and really hard to follow as a normal person. I still see him with a mixture of respect, awe, curiosity, and wonder. The thing is, none of the stuff he gave is was actually complicated. It's just a basic business dashboard. But he reinvented almost every single part of it in totally nonstandard ways that the whole project was less about coding and more about anthropology and forensic psychology.
- HlessClaudesman 3y ago
  CSI: Code Shite Investigation

kccqzy 3y ago

> After like ten or fifteen hours of trying to understand what currying is I have doubts on whether this is a sincere attempt at understanding the concept. The linked wiki page is like a five minute read and that's enough to understand the concept at a user's level. What I suspect is that something else is tripping you up and causing code readability issues; but since you didn't know what currying is you incorrectly ascribed currying as the problem.

threatofrain 3y ago
Yeah 10-15 hours is kinda crazy for an introductory topic.

deleted 3y ago

[deleted]

curry_is_easy 3y ago

Since you know JavaScript, this should help. Uncurried: ((x, y) => x * y)(3, 5) === 15 Curried: (x => y => x * y)(3)(5) === 15 If you don't understand that, your problem is that you don't understand anonymous functions (lambdas), not that you don't understand currying.

fxj 3y ago

In my experience, functional programming really shines in rapid prototyping. However, in production code I would try to avoid it, because it can confuse developers that are not used to it and also sometimes I struggle myself when decoding the short "clever" one-liner that I wrote 5 years ago. But if you want to write very powerful code withing a single line it is really great and makes you very productive for finding solutions fast. It is a bit like the Perl throw-away code we were writing in the 1990s. ;-) just my 2 ct