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Comment by viraptor | Hacker News Reader

> Indentation is a semantic property, not a visual one.

Depending on style in can be both.

    +-- semantic
    v
    def something(with aligned,
                  list of,
                  parameters):
                 ^
        visual --+

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Oh gods please don't align like this, it's just so unreadable.

Example of what that does in practice: Lines that end up wrapping almost at the end of the soft-character-limit and look like this:

https://github.com/pennersr/django-allauth/blob/c9b31ddee81d...

IMO it depends on the language. With named parameters it is very readable, and is my preference when you have functions with lots of parameters.

It breaks a fundamental assumption, which is that indent depth strictly reflects code nesting depth.

If you're going to do that, the "correct" way would be to indent each parameter with tabs to the same depth as the function declaration, and then use spaces to take up the rest of the space (i.e. the width of the function declaration). Which is admittedly ugly - but it's ugly because it reflects the ugliness of misusing indentation for alignment. It's slightly less ugly if you use an editor that displays tabs and spaces differently - Kate/Kdevelop use a nice discreet » character for each level of indentation:

  def hello_spam():
  »   while True:
  »   »   print ("Hello",
  »   »          "World")

The last line is visually aligned, but the semantic depth is the same.

I'd go with

  def hello_spam():
  »   while True:
  »   »   print(
  »   »   »   "Hello",
  »   »   »   "World"
  »   »   )

Eh? This is fairly normal in most languages. Although in the example given I might have moved the .dispatch to the next line instead.

I think all code styles which use arbitrary vertical alignment are strictly inferior to ones which use newlines and indents. The simple fact that changing `something` to `somethingElse` causes a 3-line diff is enough to convince me, but when we add the idea that hard tabs are better for a11y, it makes arbitrary vertical alignment seem completely untenable to me.

That’s a good point. If you need specific visual alignment with an arbitrary number of characters on the previous line, then spaces are appropriate. Tabs should be used for the initial semantic indentation then spaces for additional visual indentation beyond that.

(Whether visual alignment of this sort is desirable is a different question. If you want it then spaces are appropriate.)

There is a difference between indentation and alignment. Unfortunately, python chose to enforce spaces only both via the language itself and pep8.

How does the language enforce spaces only?

PEP8 was only meant as a style guide for the python standard library. Although many have unfortunately taken it as a religious text.

For that you would use tabs to align to the ‘def’ statement and spaces for the parameters. That way it keeps lining up if someone else uses different tab widths.

Move "with aligned," to it's own line and you don't need visual alignment at all, it's all semantic. Surely the extra line feed is worth elimination a whole category of alignment in code.

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