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Comment by andai | Hacker News Reader

Offtopic but what are you missing when you have to use tabs instead of spaces? I can understand different indentation preferences but I can change the indentation width per tab in my editor. And then everyone can read the code with the indentation they prefer, while the file stays the same.

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> everyone can read the code with the indentation they prefer, while the file stays the same.

Have you ever worked in a code base with many contributors that changed over the course of years? In my experience it always ends up a jumble where indentation is screwed up and no particular tab setting makes things right. I've worked on files where different lines in the same file might assume tab spacing of 2, 3, 4, or 8.

For example, say there is a function with a lot of parameters, so the argument list gets split across lines. The first line has, say, two tabs before the start of the function call. The continuation line ideally should be two tabs then a bunch of spaces to make the arguments line up with the arguments from the first line. But in practice people end up putting three or four tabs to make the 2nd line line up with the arguments of the first line. It looks great with whatever tab setting the person used at that moment, but then change tab spacing and it no longer is aligned.

On the good side, the problem of mixing tabs and spaces does normally not appear in Go sources, as gofmt always converts spaces to tabs, so there is no inconsistant indentation. Normally I prefer spaces to tabs because I dislike the mixing, but gofmt solves this nicely for me.

Please explain to me how this works for the case I outlineed, eg:

        some_function(arg1, arg2, arg3, arg4,
                      arg5, arg6);

For the sake of argument, say tabstop=4. If the first line starts with two tabs, will the second line also have two tabs and then a bunch of spaces, or will it start with five tabs and a couple spaces?

You wouldn't use an alignment-based style, but a block-based one instead:

  some_function(
      arg1,
      arg2,
      arg3,
      arg4,
      arg5,
      arg6,
  );

(I don't know what Go idiom says here, this is just a more general solution.)

Checking the original code on the playground, Go just reindents everything using one tab per level. So if the funcall is indented by 2 (tabs), the line-broken arguments are indented by 3 (not aligned with the open paren).

rustfmt looks to try and be "smarter" as it will move the argslist and add linebreaks to it go not go beyond whatever limit is configured on the playground, gofmt apparently doesn't insert breaks in arglists.

You should NOT do such alignment anyway, because if you rename "some_function" to "another_function", then you will lose your formatting.

Instead, format arguments in a separate block:

    some_function(
        arg1, arg2, arg3, arg4,
        arg5, arg6);

When arguments are aligned in a separate block, both spaces and tabs work fine.

My own preference is tabs, because of less visual noise in code diff [review].

In an ideal world, I'd think you would put a "tab stop" character before arg1, then a single tab on the following line, with the bonus benefit that the formatting would survive automatic name changes and not create an indent-change-only line in the diff. Trouble being that all IDEs would have to understand that character, and compilers would have to ignore it (hey, ASCII has form feed and vertical tab that could be repurposed...).

> In my experience it always ends up a jumble where indentation is screwed up and no particular tab setting makes things right.

Consider linting tools in your build.

It's just an example of something that the Go team took a decision on, and won't allow you to change. I mean, even Python lets you choose. I don't really have a problem with it however, even if I do prefer spaces.

There's a difference between making decisions that are really open to bikeshedding, and making sweeping decisions in contexts that legitimately need per app tuning like immature GCs.

The Azul guys get to claim that you don't need to tune their gc, golang doesn't.

Hmm ..this is why Azul's install and configure guide run in hundreds of pages. All the advanced tuning, profiling and configuring OS commands, setting contingency memory pools are perhaps for GCs which Azul does not sell.

I mean, they'll let you because the kind of customers want to be able to are the kinds of customers that Azul targets. But everything I've heard from their engineers is that they've solved a lot of customer problems by resetting things to defaults and just letting it have a giant heap to play with.

Not sure how that makes the golang position any better.

Python chose spaces a la PEP8 by the way.

PEP8 isn't a language requirement, but a style guide. There are tools to enforce style on Python, but the language itself does not.

Same thing with Go... Tabs aren't enforced, but the out of the box formatter will use tabs. PyCharm will default to trying to follow PEP8, and GoLand will do the same, it will try to follow the gofmt standards.

See:

https://stackoverflow.com/questions/19094704/indentation-in-...

You can use tabs to indent your python code. Ok, you might be lynched if you share your code but as long as you don't mix tabs and spaces, it is fine.

Same with Go, you can use spaces.

Or none at all: https://play.golang.org/p/VeEaJbJ6sYT

I don't know about anyone else, but I like aligning certain things at half-indents (labels/cases half an indent back, so you can skim the silhouette of both the surrounding block and jump targets within it; braceless if/for bodies to emphasize their single-statement nature (that convention alone would have made "goto fail" blatantly obvious to human readers, though not helped the compiler); virtual blocks created by API structure (between glBegin() to glEnd() in the OpenGL 1.x days)).

Thing is, few if any IDEs support the concept, so if I want to have half-indents, I must use spaces. Unfortunately, these days that means giving up and using a more common indent style most of the time, as the extra bit of readability generally isn't worth losing automatic formatting or multi-line indent changes.

So you are the person that ruins it for everyone (are you emacs user by any chance?). Tabs are more versatile, you can even use proportional fonts with them. Projects end up using tabs because many people end up mixing them together (unknowingly or in your case knowingly using configuration that is unavailable in many IDEs).

BTW when you mix spaces with tabs you eliminate all benefits that tabs give (for example you no longer can dynamically change tab size without ruining formatting.

If I were an emacs user, I'd figure out how to write a plugin to display tab-indented code to my preferences.

No, I used to be a notepad user (on personal projects, not shared work) (you can kinda see it in the use of indentation to help convey information that IDEs would use font or colour to emphasize), and these days use tabs but longingly wish Eclipse, etc. had more options in their already-massive formatting configuration dialogues.

The reason I asked is that I believe this behavior is what Emacs does by default (actually don't know if by default, but saw this from code produced by Emacs users) e.g.

<tab>(inserts 4 spaces)<tab>(replaces 4 spaces into a tab that is 8 columns)<tab>(adds 4 spaces after the tab)<tab>(replaces with two tabs and so on)

Unless I misunderstood what formatting you were using.

You can use empty scope braces for this task in most languages. It's not a "half-indent" but it gives you the alignment and informs responsible variable usage.

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