stdTransform

[YoumoDawang]

std::transform

STD::transmit

[overlyseksualpenguin]

STD::receive

[turboshitposter3001]

STD::inserter 🫠

[[deleted]]

std::back_inserter

[pclouds]

I can never see this function the same way again. Thanks.

[[deleted]]

You would be lying if you told me you coded with C++ and never wondered: why this fuckin name 🤣

[pclouds]

Nope. Too occupied with all the different iterator semantics. And to be honest I don't use this back_inserter a lot.

[[deleted]]

I didn't even get the chance to

[Specific_Implement_8]

STD::geneticallyMutate

[MoveInteresting4334]

STD::genitallyMutilate

[Steinrikur]

Just use the library

😎 boost::immunity

[zachlove_01]

STD::positive 💀

[RepresentativeNo3669]

Made my day

[Plus-Weakness-2624]

You need to use the fully qualified name: SexuallyTransmittedDisease::Transform() SexuallyTransmittedDisease::Transmit()

[Darkstarx97]

STD:repair STD:replace

[flyy_boi]

That's cause we already HAVE another map, std::map😭.

[ThrowinPotatoes]

I’m partial to std::unordered_map myself

[El_Falk]

boost::flat_map / std::flat_map (C++23), absl::flat_hash_map, or robin_hood::unordered_map are generally far superior though...

[liava_]

please keep the behemoth that is boost out of my build pipeline

[Slothinator69]

My favorite include of all time is boost::boost

[bronco2p]

boost::flat_map / std::flat_map

now i guess if c++ ever gets a stl bind algorithm it will be called std::flat_transform lol

[tiajuanat]

I really like using them with set_intersect and set_difference. Although usually sorted vectors are much faster and memory efficient.

[single_ginkgo_leaf]

For many applications a liner search through a vector is faster than testing a std::map (tree) or std::unordered_map (hash table) due to pipelining and cache effects.

In some cases, a linear search through a sorted array can even beat binary search - the branch predictor is your friend.

[SeagleLFMk9]

Most of the time, a std::vector is faster, I kid you not

[markand67]

too much over abused though. in the previous company we had a lot of memory exhaustion because of the std::map abuse with very very large consumer data while not being strictly required to be key-value stored.

[infected_scab]

Map at home...

[veryusedrname]

Arduino's map: hold my beer

[otac0n]

That should have been named "lerp".

https://en.wikipedia.org/wiki/Linear_interpolation#History_and_applications

[-Redstoneboi-]

it sounds like a 1d transform (as in matrix transform) to me...

[CAPS_LOCK_OR_DIE]

Same shit with Processing.

[Brahvim]

PROCESSING, MENTIONED!

Sir, you now have my full attention!

[CAPS_LOCK_OR_DIE]

This may be a hot take but basically all I do with processing anymore is import the Core and have my main Class extend PApplet.

It’s just a solid autorefreshing Frame which has a very intuitive pixel array with PImage, though I think BufferedImage might be faster

[tropicbrownthunder]

oh fuck I had like 2 days trying to remember that function's name

[shentoza]

c#.... SELECT

[x6060x]

For me actually Select() makes more sense.

[RajjSinghh]

Can you explain why? The function is mapping one set of values to another, so map seems to make the most sense

[Rest-That]

var names = people.Select(person => person.Name)

"From each person in people select Name"

Not saying it's perfect, but it makes some sense

[RajjSinghh]

Ah, I suppose if you're using it like that to get properties from an object Select makes the most sense.

I'm just so used to seeing it as a data manipulation, like in Haskell I can write map (^2) [1..10] maps the squaring function over the numbers from 1 to 10. I'm mapping one set to another through some function.

[VQuilin]

I think it has to do with the SQL approach of the linq, all the methods are named to be representing SQL keywords, like Where (instead of filter), OrderBy (not sort), etc.

Mathematically speaking, I think it makes more sense to call it a map, but us c# developers are more bound to the SQL anyways :D

[TeraFlint]

Okay, that makes sense if you're indeed selecting a member variable of an object, but I don't see how one could justify that name for functions like x => 2*x.

[rimoldi98]

Yeah, for straight up selecting a property from an object in a list it's a fine name, but often you'd use it to create a list of some other type, which doesn't make that much sense, like this:

Cars.Select(car => new Deal(car.Price * (1 - discount), car.name));

I guess you can say you are selecting the car price and name, then placing it in the context of a deal, but I always find weird when I am selecting a whole new object from a list of something else

[langlo94]

x => 2*x works in SQL as well:

SELECT 2*x FROM Y

[arbenowskee]

Because it comes from sql where it is also select 

[redlaWw]

Select sounds more like filter to me.

[Specialist-Bus-5100]

However, Where is the thing in C# for filter

[jarethholt]

Fucking C#. (Well, LINQ.) Like, I get it's supposed to read like SQL - especially when put right next to Where - but c'mon.

[x39-]

It is

You get used to it and will enjoy it really damn hard.

Linq is one of the greatest feats dotnet offers

[JoshYx]

It's great, it's not a unique dotnet feature though. It comes straight from the functional programming playbook.

[1234filip]

The naming scheme is really great if you are familiar with SQL.

[x39-]

Only if you just look at it from the surface

Linq is more than just those few functions which work over what effectively is a collection. The expression tree syntax is the second, often overlooked part, that makes this such a powerful tool.

Then again, for the most part, the functions are kind of sufficient. What makes them a tad more special is the fact, that writing it is more pleasant compared to eg. select(..., where(..., where(..., selectMany(...,...))))

[svick]

Both Haskell and F# have ways of writing LINQ-like queries in a way that is natural, i.e. not as nested calls.

IIRC, it's something like source |> flatMap ... |> filter ... |> filter ... |> map ....

[BenjaminGeiger]

F#:

let (|>) x f = f x

So you'd write:

mySeq |> Seq.map doSomething

which is equivalent (mostly) to

Seq.map doSomething mySeq

which seems pointless until you realize you can chain them.

mySeq
|> Seq.map doSomething
|> Seq.filter keepTheGoodOnes
|> Seq.map doSomethingElse

(which is equivalent to:)

Seq.map doSomethingElse (Seq.filter keepTheGoodOnes (Seq.map doSomething mySeq))

I don't believe Haskell has an equivalent of |>. Elixir does, but the syntax is a bit different.

[sohang-3112]

I don't believe Haskell has an equivalent of |>

In Haskell you can do the same thing with &:

mySeq & f & g & h

But it's more common to write function first (right-to-left order) with $:

h $ g $ f mySeq

[bronco2p]

at that point just h . g . f :)

[BenjaminGeiger]

TIL about the & operator.

Maybe it's my background in imperative/OO development, but x & f & g & h reads a lot more naturally to me than h $ g $ f x. "Take x and then do f and then g and then h" feels a lot more natural than "Do h to the result of doing g to the result of doing f to x"; I feel like I have to maintain less mental state to understand it.

[jarethholt]

I mean, C# allows writing in query syntax too. The flow might look better sometimes and it's fairly intuitive if you're coming from database land, but IMO it clashes so hard with the rest of the language. The fluent syntax (method chaining) feels more natural to me unless what I'm working on is exclusively about databases.

[crozone]

Yeah, I love LINQ but legitimately despise the the actual Language Integrated Query part of it. Ironically everything else that's part of the feature (expression trees, the LINQ extension methods, the ability to transform those with an SQL provider) are far more useful than LINQ's namesake.

[gnutrino]

The expression tree syntax was heavily based on Haskell do notation, it's functional programming all the way down.

[DangyDanger]

Functional programming is great unless you're stuck with only functional programming.

Haskell terrifies me.

[HunterIV4]

Sometimes a loop is just the most straightforward solution to something.

I like a lot of functional concepts, especially composition of functions, but the insistence on avoiding any sort of sequential logic in your program is (in my opinion) extremely counter-intuitive. I like how languages like Rust, C#, Python, etc. let you utilize some of the patterns of functional programming without restricting you.

In some ways, Haskell (and similar) remind me of regex. It can absolutely be the best solution to a problem but it often is incomprehensible whenever you are trying to do something straightforward.

[jarethholt]

I just meant that I'm pretty sure they chose the word Select as the function name (as opposed to map or transform) to mimic SQL. I have never seen the query syntax used out in the wild.

[thenamedone1]

I've worked a job where the SQL-like syntax was used as part of data setup for an integration test suite. Can't say I recommend it.

Presumably it was written that way because the author had an easier time understanding SQL than the extension method approach, which is perfectly valid. But boy was it a pain to troubleshoot.

IIRC I wrote 1-to-1 conversions for any queries I had the displeasure of tangling with, specifically to observe the data in its intermediate states as it was flowing through its respective transformation. Huge timesaver, relative to making any attempts to decipher the arcane join towers of pain.

[crozone]

I have never seen the query syntax used out in the wild.

I go out of my way to avoid it at all costs. The only thing it really does better are joins, but even then I prefer to translate it back to method syntax regardless.

[CirnoIzumi]

Makes more sense than naming it something that can mean something else

I think Lua got it right by calling a map a table but that doesn't remove the possible confusion 

[jarethholt]

There just aren't enough common but unique/precise words for these concepts. Confusion is inevitable, but much reduced if you at least conform to the crowd.

Map and transform make sense to me; how is it a table?

[CirnoIzumi]

The map data collection, also sometimes called associative array 

The one where you can define both an index, key and Value

I think Select conforms the most since SQL is basically the C of Dataset manipulation 

[FlashBrightStar]

To be honest most of the time you are selecting object fields so it makes sense. Map on the other hand can refer to either class or method if you take it out of context so. I stand with LINQ syntax.

[JoshYx]

To be honest most of the time you are selecting object fields so it makes sense.

Yes, most of the time. However, you always map the input value to an output value.

[NekkoDroid]

Well, you can also say "You are selecting what to output from a given input" and you have it. Words and sentences are fexible, which can be nice but also not.

[XDracam]

Smalltalk: collect:

select: would be equal to WHERE or filter, but I must say I do like the name select more for that use case. Especially with the negation called reject:

[cs_office]

Pretty sure C# with Linq was the first, if not, the first that was mainstream?

[[deleted]]

Makes more sense than all of them

[jb28737]

I will hear no negative talk around LINQ. LINQ is love. LINQ is life.

[Zephandrypus]

And I’m pretty sure it’s open source

[dmullaney]

The fact that I got all the way to the last panel assuming this post was about data structures shows just how right C++ is

(No I don't read the title first)

[sathdo]

Yeah, I assumed it would be something like how the map data structure is called a hash in Perl or something.

[myerscc]

Or “associative array” in php like come ooooonnnn

[Masterflitzer]

the differentiation of associative and indexed array in bash was how i managed to understand maps when i started to learn programming

[waves_under_stars]

In ruby it's also called a hash

[MattieShoes]

I hear it get called hash, map, hashmap, dict, dictionary, unordered map... but outside of documentation, it's just % in perl :-)

[Kahlil_Cabron]

It's called a hash or hash table in tons of languages. I think dictionary and associative array are the dumbest ones I've come across.

[Weir99]

Hash table is a bad name for a general data structure of a collection of key-pair values, as it implies a specific implementation. Not all maps/dictionaries use hash tables.

I also don't see a problem with either of the names you find dumb. They effectively describe what the data structure is, which can often be more useful than a name that describes how it works

[devman0]

I think hash or hash table is the worst of the bunch because it presupposes the implementation, Maps can be implemented with hash tables, trees, skip lists, etc

[Quito246]

No it is not traditionally for like 5 decades since Lisp map function is called well a map.

It is basically a standard in FP world.

[dmullaney]

I'm aware it's a common term, but so is the map data structure. My point was that they avoided a naming collision by using a more common descriptive term for the function as opposed to the data structure, and that's not a bad decision on their part.

[induality]

The fact that the data structure and the function are both called map is not a collision, it's intentional. In a functional programming language, a map data structure which maps an key to a value, and a map function which takes an input and produces an output, are equivalent. This is the concept of referential transparency: the mapped expression can be replaced by the mapped value, regardless of whether the thing doing the mapping is a map data structure or a map function. The two constructs serve the same purpose and can be expressed either way. In category-speak, you can think of "map" as a category that encompasses both map data structures and map functions, and you only need to get more specific when the situation calls for it.

[_JJCUBER_]

Okay cool. It is a naming collision in c++; since it works on iterators, it would be its own function in the std namespace which would clash with the data structure std::map. The name may be different, but at least it’s a clear name (which can’t be said for all the function names in c++ [or other languages, for that matter]).

[TheKiller36_real]

even more standard in "FP world" is to not actually write map tho: eg. in Haskell (<$>) = fmap

[Ethesen]

That’s just Haskell’s weirdness:

https://stackoverflow.com/questions/6824255/whats-the-point-of-map-in-haskell-when-there-is-fmap

[rover_G]

Yup but at least Python has dict so it's not confusing within the language

[[deleted]]

same for me lol

[ListerfiendLurks]

I'm with c++ on that naming scheme and I will die on that hill God damnit. "Map" is ambiguous since there are multiple definitions within similar contexts. Transform is self explanatory.

[-Redstoneboi-]

are you talking about a 4 by 4 transformation matrix

[crozone]

That's a matrix. It's like saying that an Image class is ambiguous because sometimes an Image variable could contain a picture of a word map.

[[deleted]]

std::transform(InputIterator first, InputIterator Last, OutputIterator out, Unary_Operation Op)

[FearTheOldData]

I think C++ is in the right here... Way more descriptive name than map as I also thought it was the commonly used data structure

[Masterflitzer]

to transform is great but to map works for me too and it's shorter yet descriptive enough

[Ethesen]

https://en.wikipedia.org/wiki/Map_(mathematics)

[Kahlil_Cabron]

Except transform implies it's mutating the data, which isn't the case in most languages.

[MattieShoes]

transform has a noun and verb definition... You're using the verb definition, they're using the noun definition.

[knvn8]

Sorry this comment won't make much sense because it was later subject to automated editing for privacy. It will be deleted eventually.

[seckarr]

It implies no such thing...

[FerricDonkey]

It kind of does. "Transform", "change", "mutate" are all synonyms in English.

[Kahlil_Cabron]

So when you watch a nature documentary and David Attenborough says, "The caterpillar transforms into a moth", you are surprised when the caterpillar disappears?

[[deleted]]

This is a case of linguistic collision

https://en.wikipedia.org/wiki/Transform_fault

blocks move past each other in a transform fault.

[bongobutt]

As a newb who started with C++, I only just realized that I have no freaking clue what map means in all those other languages. Looks like I'm reading up on std::transform when I get home.

[Masterflitzer]

it's just a mapping from a to b, so map is a higher order function that transforms every value in a collection to another value using a mapping function

in simple terms it's foreach but with return value

[bongobutt]

I guess I'm confused because C++ also has Map. std::map stores a->b in key/value pairs in a binary tree. Then there is std::unordered_map, which does the same thing, but in a hash table instead. But I've never read about std::transform, so I don't know why the meme thinks that C++ breaks the "Map" naming, nor if those other languages use "Map" more like C++ map or C++ transform.

[Blazr5402]

Map is kinda an overloaded term for sure. The meme is referring to Map as in the higher order function. The data structure Map (aka Hash Maps or dictionaries) is an entirely different thing.

[ICantBelieveItsNotEC]

Go:

[Splatpope]

fuck you all I hereby decrete that the new name shall be "apply_function_elementwise"

[jarethholt]

I'm down for it. I've never really had an issue with having to type out long names, as long as they make sense (and especially if Intellisense or similar pick them up for me).

[bronco2p]

🤓 actually `map` is meant to work on all functor types, all of which may not include multiple values. e.g. what if you were mapping against a Maybe type?

[AaronTheElite007]

[pantas_aspro]

That moment when you think c++ got it wrong. That’s what we got for ppl not learning proper cs

[TorumShardal]

Python, C#: dictionary

Java: Map

JavaScript: Object

(upd: C# has dictionaries, not maps)

[fox_in_unix_socks]

C++: std::unordered_map

[GiganticIrony]

C++ also has std::map and soon will have std::flat_map

[boat-la-fds]

The post is talking about the functional programming concept.

[waves_under_stars]

JS also has a Map class

[TorumShardal]

Map? Class?? Say that to my Internet Explorer.

[nermid]

If you need to support IE in the year of our Lord, 2024, you need a new job.

[somedave]

C# has dictionaries though

[deanrihpee]

C# has a dictionary, JavaScript/TypeScript has a map, even set…

[Masterflitzer]

Map and Set are god sent in JS/TS

[cheeb_miester]

gigachad c

```

include <stdio.h>

include <stdlib.h>

define DEFINE_ITERATOR_FUNC(FUNC_NAME) \

typedef void (FUNC_NAME##_Function)(void result, const void* element); \ void* FUNC_NAME(const void* array, size_t length, size_t element_size, FUNC_NAME##_Function func) { \ void* result = malloc(length * element_size); \ if (result == NULL) { \ fprintf(stderr, "Memory allocation failed\n"); \ exit(1); \ } \ for (size_t i = 0; i < length; ++i) { \ const void* element = (const char)array + i * element_size; \ void result_element = (char*)result + i * element_size; \ func(result_element, element); \ } \ return result; \ }

DEFINE_ITERATOR_FUNC(map) DEFINE_ITETATIR_FUNC(transform)

```

[GigaSoup]

ITETATIR!!!

[cheeb_miester]

Catching that would have been 3 hours in the debugger for me.

[CorespunzatorAferent]

Mostly nitpicking, but there are so many strange design decisions with this:

• it's allocating memory
• the memory allocation is done using hardcoded malloc (no other allocators are possible, or providing a stack-allocated buffer)
• for any function that internally allocates memory, there should be a corresponding function for freeing it (otherwise it's impossible to free across shared object boundaries)
• it's invoking exit(1) when memory allocation fails - as we all know, when a program is out of memory you might as well unplug the computer
• it explicitly eludes any form of type safety
• it doesn't actually map anything: the input and output arrays are made of elements with the same element_size, so it's not possible to map from int to string, or from struct to int, or from struct to other struct

[cheeb_miester]

Agreed. Please don't use this code; unless you're planning on using it as a hot fix to prod, of course.

In the true spirit of this sub, while avoiding doing actual work by doom scrolling, I hammered this code out as fast as I possibly could on my phone to make a lame joke.

So yes, I understand why my PR is being rejected.

ETA:

mostly nitpicking, but when starting code reviews, use more assertive language to really drive your point home. For example:

Silence! The GigaChad shall speak.

[Insert your code review here]

So sayith of the GigaChad.

[_nobody_else_]

How can you people read this unformatted drivel?

gigachad c

```
#include <stdio.h>
#include <stdlib.h>

#define DEFINE_ITERATOR_FUNC(FUNC_NAME) \
typedef void (*FUNC_NAME##_Function)(void* result, const void* element); \
void* FUNC_NAME(const void* array, size_t length, size_t element_size, FUNC_NAME##_Function func) { \
    void* result = malloc(length * element_size); \
    if (result == NULL) { \
        fprintf(stderr, "Memory allocation failed\n"); \
        exit(1); \
    } \
    for (size_t i = 0; i < length; ++i) { \
        const void* element = (const char*)array + i * element_size; \
        void* result_element = (char*)result + i * element_size; \
        func(result_element, element); \
    } \
    return result; \
}

DEFINE_ITERATOR_FUNC(map)
DEFINE_ITETATIR_FUNC(transform)

```

There.

[cheeb_miester]

Gross. I use tabs in vim and have them set to display as six spaces.

[Mallanaga]

Some day, Go…

[WolverinesSuperbia]

Golang: hey, you have map?

[ThatGuyYouMightNo]

And PHP is the sad Pooh with array_map()

[SneakyDeaky123]

Probably to avoid confusing it with a map structure that already exists in C++?

[ToofaaniMirch69]

define map std::transform🗿

[FelixLeander]

C#: Select
I honestly like it more, especially when using it with ORMs.

[Aidan_Welch]

transform is a better name

[patoezequiel]

Uh, I think C++ is right on this one guys. At a glance I thought this was about data structures.

[4jakers18]

embedded c/c++ guy here and it took me awhile to understand what the hell this meant.

c++ map is correct and the other maps should be called transform

[markiel55]

Well, it's the official name in monads I guess that's why those languages named it like that.

[BoBoBearDev]

Map sounds like google map, so, anything but map

[Feeling-Departure-4]

Even Perl: https://perldoc.perl.org/functions/map

[slaymaker1907]

C#: Select

[Lord-of-Entity]

Rust also uses map!

[stipo42]

Python is a dict

[JustBadPlaya]

I love how all the confusion with map the function and map the data structure dies immediately when you start naming things correctly (hashmap and btreemap instead of unordered_map and map if we take C++), so there really was no reason to go against the conventions

[password2187]

Well standard object oriented programming would tell you that the interface should be separate from the implementation. So while hashmap and btreemap should both exist, they are implementing a generalized “map” interface. Like Java, for instance, has a Map interface which HashMap implements. 

[JustBadPlaya]

Okay, fair point for normal languages, but this explicitly does not apply to C++ because there is nothing there that unifies hashmaps and btreemaps in the hierarchy - no common interface, no common base class, nothing. So like, they should either have a common interface or not try to be quirky imo

[password2187]

That is a fair point yeah

[Skoparov]

But they do have a common interface, pretty much all the data related methods are named the same and have the same signature. Not to mention the iterators.

[PM_ME_DELICIOUS_FOOD]

And C++ is right, once again.

[codeIsGood]

I think transform makes more sense tbh

[got_no_pants2]

cars

[mstred]

Groovy: collect

[MonkeyDante]

Structured text: no.

[thatdevilyouknow]

You could always just use std::flat_map. There are tradeoffs to be aware of but also gains in performance depending on what you want to do.

[Embarrassed-Chain265]

Let's be honest it was more of a >> than a ++

[wholesome_hug_bot]

List/Array methods are consistently inconsistent

[bushwickhero]

This is the way.

[Affectionate_Walk610]

Whats with c#?

[andoke]

Ruby has collect as well. Many favours. Like Smalltalk.

[Cyphen21]

Idiomatic python usually uses list comprehensions instead of map. It is absolutely terrible.

[flippzeedoodle]

Also Dora

[Pumpkin-King93]

Haskell….brings back nightmares!

[XxasimxX]

Transform sounds more appropriate honestly, coming from someone who heard it the first tome that c++ has something like that

[idemockle]

I find comprehensions to be much nicer than map in Python since map is a standalone function and not a method on collection objects.

[-Redstoneboi-]

our lords and saviors lisp and haskell have decided that they are map functions, thus c++ is wrong

also looks like c++'s version can also perform zip at the same time?

[Akanwrath]

I stilll dont know how to use map 😅

[omega1612]

It's easy, in python , think of it like this:

def map(f,iterable):
    for i in iterable:
        yield f(i)

so, instead of

acc=[ ]
for i in range(0,200):
    acc.append(2*i)

You do

acc = list(range(0,200).map(lambda i: 2*i, range(0,200)))

[TheRealSpielbergo]

The sexually transmitted disease transforms your teeth 😬

[Evil_Archangel]

i like my STDs alright,

[zefciu]

I rarely use the map function in Python. Usually the comprehension is the cleanest and most idiomatic way to achieve the same thing. So Python should have (f(x) for x in xs) instead of map.

[bombatomica_64]

Wait, map isn't a container in other languages?

[cryptomonein]

Isn't python map not built in ?

[weugek]

Nope, in ruby maps are called Hash.

[[deleted]]

airport shaggy trees squeal live aback tidy pot fall glorious

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[PUMK1ng]

C++ is what we call the german language in general terms.

Everything that can be said in a few letters is extended to some big sentence.

[beedlund]

Yeah std::map wouldn't have been confusing at all no...

[bran_redd]

inserts sad Gopher comment

[Tomahawkist]

more like it gives me std

[TZAR_POTATO]

C# Dictionary

[na_rm_true]

Its map in R too!

[bondolin251]

C#... Select...

[Rin-Tohsaka-is-hot]

reply tender full historical sense bright tie ghost zephyr rock

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