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Comment by rmtech | Hacker News Reader

That only works in some circumstances.

For example, suppose I init a new repo and accidentally commit my entire virtual environment, then push, then do some real work, push a few times more and then a colleague notices (after they have pulled, worked on and pushed) that the venv stuff is there.

In an ideal VCS, you would have a simple command like git purge /badfolder that would make it as if it never existed.

But AFAIK that doesn't exist, or at least the ways to accomplish that are pretty gnarly and dangerous.

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Well, first I'd argue that you are misusing the tool if you managed to commit a large chunk of unrelated code, but that's another story.

Second, I would tell you that git has a command for just your situation.

   git filter-branch

https://git-scm.com/docs/git-filter-branch

You can run a command against every commit and it will then recommit. That would let you remove, for instance, an entire subdirectory. The downside here being that you are rewriting history on something you've shared with the world and that has larger potentials for causing issues with contributors.

I guess my point is really this, git is simply one of the many tools you likely have to use on a daily basis. If you have to use a tool in your daily job it's in your interest to really grok the various ways your tool can be used. You'll want to really understand the primary use cases in detail and the less used ones you'll want to know in passing at least. That allows you to realize that something is possible with the tool, even if you don't recall the exact specifics. A machinist would have the Machinery's Handbook, a programmer will have multiple internet references. Maybe the real point is that it's _ok_ to not know the exact syntax and need to reference it for more esoteric operations.

I use an x86 CPU every day for work and I have no idea how it works in detail, and thanks to the magic of separation of concerns I don't have to (perhaps apart from a few specific things like vecorizing instead of loops that I really do need to know about).

Git demanding a large chuck of user mindspace isn't an advantage for git, it's a signal that git is bad and needs replacing.

So do interpreters, compilers, package managers, virtual environments, build systems, CI systems, test frameworks, targets, hosts. Your code doesn't exist in isolation, you need to grok how it works with the codes others have written and will write.

But for each one of these, the less I have to know about its internals, the better.

The ideal option for each of these things is that it "just works". When you have to think about the internals of your package manager or your CI or your virtual environment, that's a flaw in it, not a reason to celebrate.

You want simple internals, and one would expect programmers to understand those internals. You want the userspace to do obvious things with those internals. You don't want magic in between. Understanding internals is a feature, not a bug.

I picked Debian over Red Hat since, at the time, I could understand how .deb packages worked, and look over the state of the system. Red Hat had more opaque internals. If something broke on a Debian system, rare as it was, I could go in and fix it manually. If something broke on a Red Hat system, it was generally in a binary database file, and meant a reinstall. Red Hat also broke more often, I think for very similar reasons in design philosophy.

If I were making a tool for grandma to manage her photos, that's be something different. If you're making a coding tool for 3rd graders, perhaps you want to hide more stuff too, but even there, many modern coding environments translate blockly into Python/JS/etc. code, and show the code to kids so they can see under the hood.

I have a car, and as a car user, I want thinks to just work. As a car mechanic, I'd like things to be understandable, fixable, documented, and transparent.

git is like that. It has simple internals. Once you understand them, the userspace become very understandable too. The upsides of the elegant internals far outweigh the downside of a slightly clumsy userspace, which is why it's the dominant VCS right now.

It took over precisely from things which "just worked" with a simple userspace, and clumsy internals, like SVN and CVS.

I take the view that developers shouldn't be spending their time fixing their VCS.

I use PyCharm. I don't know how PyCharm works internally. I don't even know what language it is written in. I know that it provides syntax highlighting, smart replace, code completion, etc.

Similarly, my car mechanic has a bunch of tools that he doesn't understand in detail; they have interfaces (like a gauge on a pressure sensor).

Progress requires these interfaces, it requires these abstractions, and over time I'm pretty confident that we'll get a better VCS than git that has better, more user-friendly abstractions and it will take over the market.

It comes down to your distance from a specific 'tool' or system.

You aren't writing x86 assembler. You are presumably writing some other, higher-level language. I would fully expect you to know that language in detail and even better to understand the performance implications of the choices you make in that language. Knowing the lower level details helps there, but it's not 100% required.

With git, it's something you _directly_ interact with so I would expect you to understand it in great detail.

> With git, it's something you _directly_ interact with so I would expect you to understand it in great detail.

Yes, you are describing what is broken about git: its abstractions are leaking too much so people who touch it have to know all its internals.

I touch x86 assembler every time I run high-level code, it's just that other kind folks have gone to a lot of effort to make it so that I don't have know how the internals of that low-level stuff work.

Abstractions allow people to be productive without knowing in great detail how absolutely everything in the universe works. A good tool has simple, non-leaky abstractions with a simple interface. Git is not a good tool.

Yes but filter-branch is horrendous and could very easily result in unintended side-effects, as well as potentially being very slow. I think this command is a great example of the problem; what a user really wants is an undo button but what git gives them is this thing.

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