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Functional programming jargon in plain English

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Re: Functional programming jargon in plain English

#51

Post by IAmYourDensity »

goto11 wrote: post #31
jstx1 wrote: post #5

Earlier quoted context omitted.

Why do monads come up so often when people talk about FP? Is it a meme or are they really an important and difficult to understand concept?

They are used pervasively in Haskell, less so in other functional languages. In Haskell, you can't write a "Hello world" program without using monads, so you cant really avoid learning about them. IMHO monads are only really useful in Haskell because it has specific built-in syntax sugar to support them. Without this syntax sugar, they would be very cumbersome to use. So it's not really the monad type per se which is…

And the reason you can't write "Hello world" in Haskell without using a monad is that functions in Haskell are "pure", meaning they cannot have side effects like outputting to the console.

Preventing side effects, including reading and writing global state, helps prevent bugs and makes it easier to understand and refactor Haskell code. Some would argue that the extra layers of abstraction from category theory and unpredictable order and number of lazy evaluations can actually make it harder to understand and refactor Haskell code.

Anyway, in order to perform I/O in Haskell, you evaluate your pure functions as a sequence of actions that are executed by the Haskell runtime. The construct that helps you build the sequence of I/O actions and allows you to bind their intermediate values to arguments to be used by subsequent actions is called the 'IO' monad.

Re: Functional programming jargon in plain English

#52

Post by shikoba »

mjburgess wrote: post #25
shikoba wrote: post #16

Earlier quoted context omitted.

> Functor = context for running a single-input function No a functor is a "function" over types that can transport the arrows: (A -> B) -> (F A -> F B) for a covariant functor (A -> B) -> (F B -> F A) for a contravariant functor With the sum and product there is also the exponential: B^A = functions from A to B

In my simple language, `F` is that context. And (A->B) is a single-argument function. // Int -> Float oneArgFn(x) = x + 1.1 // List of Int -> List of Float ctxOneArgFn(xs) = ListFunctor(oneArgFn, xs) //ie., map()

You're just reducing my idea to a specific case. You missed the generalized idea.

Re: Functional programming jargon in plain English

#53

Post by mtreis86 »

mgaunard wrote: post #47

Looked at first one (arity), saw "argument" when what was actually meant was "parameter", and therefore dismissed the document. If you want to make a glossary, at least try to be precise.

They said 'a function takes arguments', which is correct. The arguments are passed into the function, aligning to and being bound to the function's parameters. So arity applies both to arguments the function can take, and the parameters the function has.

Re: Functional programming jargon in plain English

#54

Post by saithound »

goto11 wrote: post #36

Pet peeve: The word "just" when used to gloss over something with the author don't know how to explain. Using "just" shift the burden from the author to the reader, since it signals it is the readers fault if they don't understand. > A homomorphism is just a structure preserving map. In fact, a functor is just a homomorphism between categories as it preserves the original category's structure under the mapping. How a…

Mathematicians use "just" with a specific meaning: it is not used to gloss over something that the author doesn't know how to explain. It has a purpose, useful for mathematically trained readers.

For suc a reader, "a homomorphism is just a structure preserving map" makes it clear that "homomorphism" and "structure-preserving map" can be used interchangably, and that by understanding one of the concepts, you'll immediately understand the other as well.

When you got rid of the word "just", you got rid of this connotation and changed the meaning of the sentences.

E.g. the sentence "a functional is a linear transformation" is correct; but not all linear maps are functionals, so writing "a functional is just a linear transformation" would be plain wrong in a mathematical setting.

Re: Functional programming jargon in plain English

#55

Post by josu »

goto11 wrote: post #36

Pet peeve: The word "just" when used to gloss over something with the author don't know how to explain. Using "just" shift the burden from the author to the reader, since it signals it is the readers fault if they don't understand. > A homomorphism is just a structure preserving map. In fact, a functor is just a homomorphism between categories as it preserves the original category's structure under the mapping. How a…

Be the change you want to see in the world haha

https://github.com/hemanth/functional-programming-jargon/pul...

Re: Functional programming jargon in plain English

#57

Post by ncmncm »

stingraycharles wrote: post #50
ncmncm wrote: post #44

Earlier quoted context omitted.

We need an explanation why we should care about support for currying. Where it is really just to support variadic argument lists, it is a big hammer for a little problem.

And precisely because of the code sample, it should be obvious that currying is not the same as variadic function arguments. Instead, it allows for very concise partial function application, as demonstrated by the code. I can just call any function with a subset of its arguments, and it automatically returns a “new function” which you can call with the remainder of the arguments. It allows you to reason about calling…

Saying "it allows for very concise partial function application" does nothing but repeat the definition. It does not, in particular, offer any reason to want that. What is so special about the first argument, that I want to fix it? Why not the third? Why is what I do to fix the third not just as good for the first?

Pattern matching is a good example of a language feature included because they could not figure out how to provide features expressive enough to be composed to implement the feature in a library.

Re: Functional programming jargon in plain English

#58

Post by bjarneh »

goto11 wrote: post #36

Pet peeve: The word "just" when used to gloss over something with the author don't know how to explain. Using "just" shift the burden from the author to the reader, since it signals it is the readers fault if they don't understand. > A homomorphism is just a structure preserving map. In fact, a functor is just a homomorphism between categories as it preserves the original category's structure under the mapping. How a…

> The word "just" when used to gloss over something with the author don't know how to explain.

Never thought of that before, but it's certainly true. Always hated when we got cryptic explanations for the difficult things, and elaborate explanations for the stuff everyone understood anyway at the university. I guess professors have to explain things they don't fully understand from time to time

Re: Functional programming jargon in plain English

#59

Post by minraws »

cinntaile wrote: post #48
goto11 wrote: post #36

Pet peeve: The word "just" when used to gloss over something with the author don't know how to explain. Using "just" shift the burden from the author to the reader, since it signals it is the readers fault if they don't understand. > A homomorphism is just a structure preserving map. In fact, a functor is just a homomorphism between categories as it preserves the original category's structure under the mapping. How a…

This is left as an exercise to the reader.

Just to be clear, that's quite literally the Wikipedia definition.

> In algebra, a homomorphism is a structure-preserving map between two algebraic structures of the same type (such as two groups, two rings, or two vector spaces).

Not sure if this is rude but many definitions there seem a bit, not plain English.

I am assuming we are aiming for something close to ELI5 if the title says plain English.

Ofc that could not be what the author intended and is just but that's how inferred the title.

I will see if I can find time to improve and send some PRs for the ones that are in deep need of simplification, hopefully OP is open to discussing changes.

Also like Arity, Arity is not just for functions, it can sometimes be interchanged with Rank and apply to even Types. higher ranked types. higher arity types... I do understand they are not something most people like, because of their issues but that's not a complete definition so I assumed it was for the means of simplifying to explain to beginner programmers. [reference to issues with HRTs](https://www.sciencedirect.com/science/article/pii/S016800729...)

Again this is not meant to be rude to the author, just hopefully the title could be better formed to explain the intent of the work. Or my opinion might be minority and we can decide against it as well ofc.

Re: Functional programming jargon in plain English

#60

Post by plasticchris »

saithound wrote: post #54
goto11 wrote: post #36

Pet peeve: The word "just" when used to gloss over something with the author don't know how to explain. Using "just" shift the burden from the author to the reader, since it signals it is the readers fault if they don't understand. > A homomorphism is just a structure preserving map. In fact, a functor is just a homomorphism between categories as it preserves the original category's structure under the mapping. How a…

Mathematicians use "just" with a specific meaning: it is not used to gloss over something that the author doesn't know how to explain. It has a purpose, useful for mathematically trained readers. For suc a reader, "a homomorphism is just a structure preserving map" makes it clear that "homomorphism" and "structure-preserving map" can be used interchangably, and that by understanding one of the concepts, you'll immedi…

Sure, but the title does say plain English so this would be the sort of thing the author is trying to avoid. If that’s the meaning just write all a are b.
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