> It is far and away the most common footgun novices run into when I'm answering questions about why their code doesn't work.
It was, in my experience, before Python 3 clamped down on mixed spaces on tabs; before the `SyntaxError`s got better (for example the handling of `try` without `except`); and before VSCode got so popular (such that all the novices were using who-even-knows-what random editor and you had to figure out every time how they were actually producing the indentation, whether it does/can convert tabs to spaces).
And, oddly enough, before LLMs. Not so much because they explain anything all that well, but because lazy clueless people now get correctly indented code generated in-place rather than copying and pasting from Stack Overflow and not having any clue how to make the pasted code line up properly.
But now I far more often see people who are clueless enough that they can't distinguish the REPL from a command line ("why is `pip install ...` a syntax error?"), or are struggling with whatever is the latest attempt by the Python team to make Python easier to install and manage on Windows, or who seemingly can't wrap their head around the idea that Python has to know where on disk to look for the installed libraries (or why it won't work to just put everything in the system environment). And in terms of the language itself, probably the biggest stumbling blocks are things like command-query separation ("why can't I `foo.append(bar).append(baz)`?") and just using functions properly (which typically boils down to "why doesn't `return foo` let me refer to `foo` in the calling function?", but generally stated completely differently).
Whitespace cleanliness is only part of the problem. The much bigger issue is the fact that the ending of a block is invisible. This leads to several problems:
1. It becomes much more difficult to tell beginners where the end of a block is, because the ending of the block isn't something you can describe verbally. You have to point to it instead.
2. Students who might be prone to using the wrong number of "}" or "end" tokens to close a block will instead un-indent the wrong number of times. It doesn't prevent the kinds of mistakes that mismatched parens tend to cause.
3. When closing a block, the thing you're trying to align a prior block with might not be on screen any longer. I don't know why, but I've seen more off-by-one spacing gaffes after the close of a nested block than I ever expected to see.
That said, I don't doubt that Python arrived at the choice of whitespace blocks empirically. However, I highly suspect that the majority of the users learning how to program in the late 80's and early 90's were familiar with monospaced text, which was ever-present in most productivity applications of the day, and thus easier for them to reason about.
And to be clear, I don't really care that much about Python's whitespace blocks. I don't like them, but I'm at the age where I feel like quibbling over minor syntax gaffes is beneath me, and Python is my top "swiss army knife" language when I need a job done quickly. My only point is that I feel like whitespace blocks are a relic of the time when they were developed, and I don't think they are as beginner friendly as advertised.
EDIT: After stepping away from the post, I realized that in my perfect world, a beginner language would look a lot more like Lua than Python. Then I remembered how popular Roblox is, and how popular Garry's Mod was before that. Given the success of those platforms, there might be something to it.
It was, in my experience, before Python 3 clamped down on mixed spaces on tabs; before the `SyntaxError`s got better (for example the handling of `try` without `except`); and before VSCode got so popular (such that all the novices were using who-even-knows-what random editor and you had to figure out every time how they were actually producing the indentation, whether it does/can convert tabs to spaces).
And, oddly enough, before LLMs. Not so much because they explain anything all that well, but because lazy clueless people now get correctly indented code generated in-place rather than copying and pasting from Stack Overflow and not having any clue how to make the pasted code line up properly.
But now I far more often see people who are clueless enough that they can't distinguish the REPL from a command line ("why is `pip install ...` a syntax error?"), or are struggling with whatever is the latest attempt by the Python team to make Python easier to install and manage on Windows, or who seemingly can't wrap their head around the idea that Python has to know where on disk to look for the installed libraries (or why it won't work to just put everything in the system environment). And in terms of the language itself, probably the biggest stumbling blocks are things like command-query separation ("why can't I `foo.append(bar).append(baz)`?") and just using functions properly (which typically boils down to "why doesn't `return foo` let me refer to `foo` in the calling function?", but generally stated completely differently).