Comment by flohofwoe
13 hours ago
For games, C++ becomes a much simpler language since game code bases usually ignore the C++ stdlib (at least mostly, and for good reasons, e.g. see [0]). And without the stdlib C++ is actually kinda-sorta okay-ish.
Related, the main problem with the C++ ecosystem is that everybody carves out their own language subset, so it's not one ecosystem but many ecosystems with contradicting styles and language/stdlib subsets. This makes code reuse via libraries much harder than it should be.
[0] https://hftuniversity.com/post/the-c-standard-library-has-be...
I fully agree. In my personal project, I ended up using the STL to get off the ground, but in the end I replaced pretty much everything with custom-written code.
Once you get rid of the STL, compile times get so much better. With modern c++23 features, templates actually become really convenient to write, and at the core there is a really useful and pleasant to use language.
I try to avoid c++ libraries and instead rely on c-style APIs. Usually the c++ style libraries force you into using the STL, which comes with a heavy tax on compile times, without much benefit in comfort of use.
What, you rewrote std::deque? Whew!
Deque is one of the easier ones.
I echo the parent commenter - the STL has a massive negative impact on compile times. And for what? The STL is not even fast. The way the standards are written, std::unordered_map has to be implemented as a tree rather than a flat open-addressing hashtable, which would've been far superior due to cache locality.
For my own project I rolled my own string, string_view, map, set, optional, variant, and vector. Only took maybe a day. And that day has paid dividends, as my clean debug builds literally take 3 seconds now.
Rewriting at least std::vector was a standard way to prep for a Google interview. And std::map if you wanted bonus points or a level up. Also, really interesting to do.
If you don't use the STL you end up re-implementing it yourself. Usually poorly.
> Usually poorly.
On the contrary. You can focus exactly on the features the higher level game code needs. The C++ stdlib is (for the most part) poorly designed, usually poorly implemented, the main reason for slow build times, and its complexity explodes because it needs to consider all edge cases that most code bases don't ever trigger.
A specialized dynamic array class in a few hundred lines (at most!) and with just the required features is much more useful than the 20kloc monster that's pulled in with `#include <vector>` and which doesn't even do bounds checking in the 'idiomatic' usage.
Saying it doesn't even do bounds checking (in release builds) is to miss one of the major points of C++ - not paying for what you don't need. It's not a mistake, it's a feature.
You complain about it not being suitable for game development in one comment but then expect bounds checking in release builds? You're sitting in multiple lanes at the same time.
NIH implementations are usually grossly inferior because as it turns out, it's quite hard to get it right and those edge-cases aren't important until you start getting bitten by them when you'd rather be shipping features.
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Yes I don't disagree that sometimes a specific container or a data structure is great for the problem. Problem is that most of the game code and related code (so tooling,editor, auxiliary engine code) does need a typical STL type functionality and then when the org has "omg no STL" blanket rule someone ends up implementing STL and that's almost always worse than the STL that ships with the tool chain. Even worse..it'll be missing features and data structures and then people have to write sub-optimal code to work around it's limitations.
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I find it hard to agree that the stdlib is poorly designed and implemented. In my entire career it has pretty much worked entirely to spec.
Yes, it can exhibit non-optimal performance, and in some specific cases (regex's especially), extremely poor performance, but that's not the same as being poorly designed and implemented, especially given the breadth of the thing.
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Which is why one of the security measures in C++26 is to make bounds checking idiomatic, finally.
The STL is not good if you want performance or predictable behavior. The issue is in the specification and the requirements placed on certain algorithms and data structures. It’s easy to beat unordered_map for example with an open addressing hash map, small vector optimization can’t be implemented in vector due to standard requirements, etc.
some of the STL is easy to improve on. For example, std::unordered_map performs poorly due to pointer stability requirements in the standard. Most performance sensitive C++ codebases will use something like abseil's hash maps instead.
Just a heads-up: if you're already using boost, boost::unordered now has open addressing containers (unordered_flat_map and unordered_flat_map) and they are among the fastest.
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Which is worse? std's mess or one you control? I'd take any random game engine's STL over std any day.
C+ Standard Template Library is the best designed part of C++ library. It was designed by Alexander Stepanov.
https://en.wikipedia.org/wiki/Alexander_Stepanov
So, a few things (aside from the whole nomenclature argument already in another reply)
1. Stepanov's generic programming is a good idea. Every language you've seen with "generics" that's his idea, to the extent "The STL" is generic programming, everybody agreed it's a good idea.
2. But the STL is very old now, so while the idea is good, this is one of the oldest (Stepanov had tried this in other languages before C++) implementations and so other implementations are often better, because they've learned from experience
3. As well as pretty good generic algorithms, the STL also provides a lot of container types (what Rust would call collection types) and these vary not between "excellent" and "mediocre" but between "mediocre" and "inexplicably terrifying". The most charitable explanation is that they're just intended for teaching. If you teach DS&A to a Computer Science class you want the Extrusive Doubly Linked List to teach in class. If you write software you almost certainly never need this type, but it's front an centre in the C++ STL.
There's a single "I guess I would use this" container type, std::vector. It has an insane special case for bool, because WG21 are idiots, but it's otherwise a good enough growable array type and it's not worth building your own instead given the constraints.
Everything else is silly, or bad, or both. std::unordered_map feels like a hash table I made in class in the mid 1990s, but it's actually the provided standard hash table container in C++ 11 onwards. std::list is just that extrusive linked list for some insane reason. The Microsoft standard library maintainer STL could not offer me any justification for what std::deque is actually supposed to be for.
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It has some very useful principles, but also some super-annoying gaffes and mis-design aspects. One example: Allocators. What a mess! Or the fact that if a map lookup fails, an exception is thrown. I can't count the times I've had some app just bail out on me with an at() exception, because the author neglected to handle it (and the map/unordered map interface did not force them to). That does not detract from Stepanov's important work.
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Nowadays also used by many of us (wrongly) to refer to the overall C++ standard library, instead of what was inherited from C.
Your citation refers to the register keyword and trigraphs, among other language features -- the author seems to have forgotten his own point, among a number of other inconsistencies and contradictions, and at times seems to go out of his way to come across as a jerk, e.g., "This is what fifteen years of standards work on an eight-letter keyword looks like".
People love to rag on the standards committee. I was on X3J11, the C Language Standards Committee, in 1989 ... in fact, due to alphabetical order I was the first person on the planet to vote to approve the C language standard -- the one that first standardized register and trigraphs. Standards work is hard and everyone hates you for it.
The C Committee is fine and doing great work! The C++ Committee could actually learn a thing or two from how things are done on the C side.
Like strings and arrays?
Or _Keywords with an additional header file?
Maybe something_ names as proper namespaces are too hard?
One could mention better testing before adding features to the standards, but then C99 VLAs happened.
That article probably isn't the best source to cite. You can look at the discussions on it elsewhere, although I'd just dismiss it as slop.
The standard library is mostly fine to use unless you have specific needs.
The bit about libraries is nonsense, sorry.
The article might be slop, but the problems described in it are definitely real ;)
Grossly exaggerated or misunderstood in many cases. Some of their arguments are just flat-out wrong.
I mean, why are they blaming the standard library for inherent properties of linked lists? Yeah, you don't want to use them without good reason. That's just called picking the right data structure for the job, not a flaw with the standard library.
Some of the other choices were tradeoffs between performance and usability. The standard maps have stable iterators, whereas third-party implementations almost never do because you can write faster implementations if you're willing to live without those guarantees. Was it the right choice in hindsight? Maybe, maybe not.
I'd personally like to see a namespaced versioned standard library but like that's ever going to happen
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