Fstrings.wtf

by darkamaul • 1 year ago

433 133 1 year ago

Cute quiz! As a reminder, if you're doing anything even slightly complicated with f-strings (beyond :x or var=), leave a comment.

zahlman9• 1 year ago

Ohg abg orgjrra gur oenprf! ;)

Disposal8433• 1 year ago

As someone who works on a codebase with almost no comments, please leave a comment for every block of code that does something and explain why (1 comment for every 5 or 10 lines of code should be fine).

And for regex you have this in some languages: https://docs.python.org/3/library/re.html#re.X

cluckindan5• 1 year ago

Please include any technical and especially business reasons in the ”why”, please.

elteto• 1 year ago

Hey, I’m doing complicated things with f-strings so I’m leaving a comment as requested.

zahlman9• 1 year ago

21/26, with a couple of sleep-deprived brainfarts and a misclick. Learned very little, although I had the wrong reasoning for one of the ones I got right (tested afterward). I don't even use the {var=} thing or walrus operator, though.

I would definitely not do nearly as well on jsdate.wtf. I really still think JS has the greater WTFs.

the_mitsuhiko2• 1 year ago

I was not sure about the difficulty. Python has some really weird behaviors with some of the custom __format__. For instance f"{'None':<010}" will pad out, but f"{None:<010}" will error. The only one I ended up putting in is the gotcha that bool is an int subclass and gets the int behavior for custom format parameters (which almost sounds like a bug). f'{''''''''''''}' is also a weird one, but that is mostly an issue with the string concatenation syntax and not fstrings :)

There definitely are some more odd / confusing ones.

OJFord2• 1 year ago

For instance f"{'None':<010}" will pad out, but f"{None:<010}" will error.

Is that any different than being surprised that 1 + 1 is 2 and '1' + '1' is '11'?

Retr0id• 1 year ago

I made a mistake on 7, but wouldn't have done if I had syntax highlighting.

istrice• 1 year ago

Nice quiz! I admit I was surprised a couple of times (especially with f"{1<5:1<5}"), many of these features are hardly ever needed

Liftyee• 1 year ago

I like this quiz format much more than just reading a doc because I get to guess what it might do before finding out, which reinforces how well I remember it. As a Python amateur I had no idea fstrings were so powerful!

frickit• 1 year ago

These games just reinforce that I’m an idiot.

meinersbur• 1 year ago

Just learned about the ellipsis statement and the !a modifier (I already knew !r and !s).

tialaramex2• 1 year ago

String interpolation is one of those features like inference where if you've had it before then going without is very annoying, and so you add some and that's nicer, then you add more, each step seems like it's an improvement, and then one day you realise you're looking at unintelligible nonsense and you say "Oh no, what have we done?"

This is unusual, often CS would love to have as much of whatever as we can, but mathematics says no that's literally or practically impossible - but here both none and lots are awful and shouldn't be permitted.

One option, which Python and C# both picked is, well, leave it to taste. You can write sixteen pages of layered expressions in the uncommented interpolated string and it'll work, but your colleagues will curse your name and plot your destruction. Or at least you'll fail code review if you enforce such things.

Another option, in standard C++ 23 today for example, is refuse to take even the first step. You can have rich formatting, but standard C++ does not provide interpolation at all, if you want to format six parameters then pass them as parameters.

I'm happy with Rust's "Only a tiny bit of interpolation" where you can interpolate only identifiers, not any other expressions, but that's definitely more interpolation than some will be happy with, yet of course in some cases it's not quite enough.

Waterluvian• 1 year ago

Purity and practicality are at odds and every language finds a different balance between the two. There is no one correct balance so busy minds will inevitably have loud opinions they want accepted as the one correct balance.

almostgotcaught5• 1 year ago

busy minds

cute pun but compared to busybodies it really hides the implication (i thought you were talking about people with adhd at first).

sublinear• 1 year ago

CS would love to have as much of whatever as we can, but mathematics says no

What does this have to do with either topic?

cvoss2• 1 year ago

I, too, struggled to understand the meaning of this sentence. I can parse it, I guess, but any meaning I try to guess for it is either implausible or irrelevant.

tialaramex2• 1 year ago

Take optimisation, another task like interpolation which the machine does to transform our program text into an executable

We'd like exhaustive optimisation, in fact that can't be done and today we're used to a relatively aggressive optimisation which would not have been possible fifty years ago, but we're nowhere close to optimal for non-trivial programs.

Or correctness, it seems as though global static analysis should be possible, at least for something modest like a typical Unix utility - nope, that is known to be mathematically impossible for even quite modest software, only local analysis is at least plausible and its effects are much more limited than we might hope.

veber-alex• 1 year ago

I hate Rust's solution because it's not a solution at all.

Interpolation only works in a small subset of cases, which makes you constantly having to think whether it can or can't be used in the current situation and requires endless churn when refactoring code.

At the very minimum, they need to allow it to work with field access.

On the other hand, in python, while examples like this site exist and are funny/weird/quirky in practice nobody cares, and they just enjoy using fstrings.

Philpax• 1 year ago

It's pretty straightforward? You can interpolate a variable in scope and apply modifiers to it. You can't interpolate arbitrary expressions (which field access would be). Alternatively, you can interpolate an arbitrary identifier, then specify a value for that identifier in the arguments.

The key is "identifiers, not expressions."

almostgotcaught5• 1 year ago

String interpolation is one of those features

70% of these "wtfs" aren't about string interpolation but just python's syntax for string.format

https://docs.python.org/3/library/string.html#format-string-...

zahlman9• 1 year ago

"String interpolation" is a term for the purpose that the string.format syntax serves.

zahlman9• 1 year ago

then you add more, each step seems like it's an improvement, and then one day you realise you're looking at unintelligible nonsense and you say "Oh no, what have we done?"

I've never found it difficult to keep them in check. I still can't fathom a use case for nesting f-strings within an f-string substitution, for example. And probably the only format specifier I commonly use is `:02x`.

Doxin• 12 months ago

I still can't fathom a use case for nesting f-strings within an f-string substitution

Isn't that mostly just a side effect of using the proper full python parser for F-strings? The syntax for what was allowed inside an F-string kept getting more and more permissive, until they just decided to permit ~all of python inside an F-string.

orthoxerox• 1 year ago

One option, which Python and C# both picked is, well, leave it to taste.

Every time I need to format a number or a date in C#, I just hit the documentation. I refuse to memorize its terrible formatting mini language.

Timwi3• 1 year ago

Or you could just write your own if you think you can create one you'll be happier with. C# provides IFormatProvider for this exact purpose and I've honestly not seen that level of customizability elsewhere.

whartung• 1 year ago

  > then one day you realise you're looking at unintelligible nonsense and you say "Oh no, what have we done?"

I think that’s a bit of what the Java String Template folks went through.

It was a pretty cool system (on the surface, not having used it, I liked what I saw), but they pulled it straight out. They felt the direction was unworkable. Pretty interesting considering I think the demand for such a facility (as mentioned, once tasted, hard to let cider), plus the work involved to date. Interesting they found it irredeemable to shelve it entirely and back to the white board.

PaulHoule2• 1 year ago

I tend to stuff complicated strings (SQL queries and such) into resources (files that get baked into the JAR) and implement some kind of templating for them if I think it's necessary.

cluckindan5• 1 year ago

If this was JavaScript syntax, most of the comments would be lamenting the unintuitive syntax and weird features.

crazygringo• 1 year ago

Right, I assumed the real point the quiz was making is that Python is as full of footguns as JavaScript, since I've seen this type of thing for JS a bunch of times.

Not saying I agree, but was definitely expecting that to be the main topic of discussion here...

jvolkman• 1 year ago

But if it were Perl, they'd be celebrating.

somat• 1 year ago

On the subject of javascript template literals.

Do they really not support the equivalent to

    let template = 'hello ${name}';
    let n1 = template.format({ 'name':'joe' });
    let n2 = template.format({ 'name':'bob' });

I am not really a javascript programmer. but I was writing some and wanted to store a bunch of templates then fill them out dynamically and was unable to figure out how to do it with the native javascript template system. So I ended up having to write my own. As it appears to be a huge obvious hole in missing functionality, I have to ask. Am I holding it wrong?

While writing this up I was rereading the mdn page on template literals, perhaps tagged templates would do what I wanted, I don't remember why I did not use them(I think it is still not possible to store the template), but on first glance, yeah, lamentations about the unintuitive syntax and weird features.

cluckindan5• 1 year ago

Tagged templates probably won’t help, or will be quite messy. But you can just use a thunk with some parameter destructuring:

    const tpl = ({ name }) => 
      `hello ${name}`;
    const n1 = tpl({ name: "joe" });
    const n2 = tpl({ name: "bob" });

Or if you don’t like the duplication of property names, you could do it without destructuring:

    const tpl = (o) => 
      `hello ${o.name}`;

Look for the free online book ”You don’t know JS”, it is good reading.

wolfgang42• 1 year ago

I think what you want is to just make a function and pass it the values:

  const template = ({name}) => `hello ${name}`;
  const n1 = template({ name: 'joe' });

(Tagged templates won’t help here because the bit in curly braces is an expression which is evaluated to a value first; you’d need some kind of macro system to get access to the original variable name at runtime.)

va1a2• 1 year ago

More specific shenanigans aside, JavaScript will always be the king of unintuitive syntax. Some of these f-string tidbits are very much strange, but you'd have to be implementing something specific to encounter them. Meanwhile over in JS you're still waiting for your dependencies to install so you can compare two arrays.

cluckindan5• 1 year ago

That is exactly the kind of unfounded, strawman-riddled criticism I was after ;-)

What does an algorithmic task such as array comparison have to do with language syntax? The answer is nothing.

Sure, some languages might have builtins for comparing certain things, or doing intersections/differences, but those only apply to arrays of primitives, and even in those cases the utility of the builtins completely depends on the use case, and those builtins still have nothing to do with syntax.

WithinReason• 1 year ago

thanks I hate Python now

kosolam• 1 year ago

I doesn’t exist. Lol

psychoslave2• 1 year ago

Awesome, makes me glad I didn't touch Python for years now.

Hell is paved with good will I guess. Probably Justine should update https://justine.lol/lex/

skrebbel• 1 year ago

makes me glad I didn't touch Python for years now.

C'mon, every language has quirks.

bogtog• 1 year ago

Many of these are desirable features!

sfink3• 1 year ago

...if you think Python is irregular, what the heck are you using for scripting instead??!

psychoslave2• 1 year ago

Regularity, as the number of rules a system rely on, is not the only variable, and not even the effectively most significant one, when it comes to language ergonomic. Just like terseness, it's an easy to measure and easy to make low in ways that are actually working against ergonomy.

If you look at Justine post, Ruby is given as the hardest to make highlighted correctly. Much of it I guess however pertains to the many ways it's possible to switch to in place string feeding. It's harder to deal with for automated parsers, but it's generally not pushing human writers to encode in a way that is later harder to interpret by fellow humans with many surprising pitfalls to keep in mind. It doesn't mean that Ruby doesn't have any pitfall, but at least its community is using this low level of suprise as a guiding principle.

Optimizing for the shortest encoding string is missing the point that the biggest cost will be how much time some human being will need to understand correctly what was the intended result. Python used to emphase easy to read over syntax tersrness golf. Looks like it changed.

Now, they are people who love that kind of golf, I'm sure. So for them, that's certainly good that Python is digging that rabbit hole.

It's ok not everyone share the same taste, isn't it?

CivBase• 1 year ago

16/26

I always use a reference when doing anything non-trivial with format strings of any kind and this quiz confirmed I should keep doing that.

Also I've been using Python professionally for over a decade but TIL about the Ellipsis object.

neoden• 1 year ago

How can I setup a linter to prohibit stuff like this in my code base?

hackyhacky• 1 year ago

Just use Python 3.5.

jwilk• 1 year ago

str.format() can be cursed too, e.g.:

  >>> '{:{}{}}'.format('m', 'o<2', 3)
  'moooooooooooooooooooooo'

serf• 1 year ago

the reward for 100% should be a directory of languages that deals with strings in a sane/singular/readable way.

it's cool that half of those features are there. it's not cool that half the devs that read the thing after creation are going to have to look up the f string features.

Y_Y• 1 year ago

I've compiled a directory of those lamguages here:

nojs• 1 year ago

This is the first special feature of f-strings: adding a trailing equals sign lets you print out the expression and what it evaluates to.

    >>> foo='bar'; print(f"{foo=}")
    foo='bar'

Wow, never knew you could do that.

black_puppydog• 1 year ago

such a boon for print(f) debugging. :)

jszymborski• 1 year ago

No more will I have to

print("foo", foo)

ck45• 1 year ago

Python release notes are really worth reading, for me there's usually some "positive surprise"

The = support was added in Python 3.8: https://docs.python.org/3/whatsnew/3.8.html#f-strings-suppor...

lillecarl3• 1 year ago

If you come from verbosity land C# release notes are magically good as well, always some way to reduce boilerplate while maintaining "implicit verbosity" which your proprietary LSP resolves 100% correctly.

I'd prefer writing C# if I had the Linux interaction libs Python has. I'm too dumb to write syscall wrappers

ahartmetz2• 1 year ago

Incredibly common for debug output. In C++, I have made it a habit to just copy the expression, once with quotes and once without. It's informative and doesn't require thinking, or, well, I'm still working on that.

stkdump• 1 year ago

It's the kind of thing you do with macros in C++.

acdha• 1 year ago

It makes me sad that the PEP for the equivalent behaviour for function keyword arguments wasn’t accepted. It’s really common to see foo(bar=bar) and I think it’s not only cleaner but would help see subtle differences if that was foo(bar=) because it would make the cases where some arguments aren’t simply being passed through more obvious: foo(bar=, …, baaz=baaz.get_id()) avoids the most interesting detail being easily missed.

lillecarl3• 1 year ago

Do you know why? I didn't know of the fstring one either but I've thought to myself across many languages that a way to print the expression (or just varname in my head) with the result should exist.

roenxi• 1 year ago

And it seems like a bad idea because of that wow factor - it isn't really adding enough to justify having surprising behaviour. It is more likely to be a bug than a feature.

It'd be better to just let people implement their own function that prints a subset of locals(), or provide a standard function that does the same.

stephenlf• 1 year ago

Much easier than date.wtf

ciupicri• 1 year ago

From JavaScript i.e. https://jsdate.wtf/ ?

ejiblabahaba• 1 year ago

Learned a few tricks that I'm sure are buried on fstring.help somewhere (^ for centering, # for 0x/0b/0o prefixes, !a for ascii). I missed the nested f-strings question, because I've been stuck with 3.11 rules, where nested f-strings are still allowed but require different quote characters (e.g. print(f"{f'{{}}'}") would work). I guess this got cleaned up (along with a bunch of other restrictions like backslashes and newlines) in 3.12.

F-strings are great, but trying to remember the minute differences between string interpolation, old-style formatting with %, and new-style formatting with .format(), is sort of a headache, and there's cases where it's unavoidable to switch between them with some regularity (custom __format__ methods, templating strings, logging, etc). It's great that there's ergonomic new ways of doing things, which makes it all the more frustrating to regularly have to revert to older, less polished solutions.

sfoley• 1 year ago

Yeah I consider that one to be a trick question. I knew same-quote-style nested f-strings were coming, I just didn't know which version, and I still use the `f'{f"{}"}'` trick because I want my code to support "older" versions of python. One of my servers is still on 3.10. 3.11 won't be EOL until 2027.

zahlman9• 1 year ago

I guess this got cleaned up (along with a bunch of other restrictions like backslashes and newlines) in 3.12.

Yes: https://docs.python.org/3/whatsnew/3.12.html#whatsnew312-pep...

ctoth• 1 year ago

One thing I keep not understanding is I see colleagues or AIs put f-strings in logger calls! Doesn't the logger do lazy interpolation? Doesn't this lose that nice feature?

mixmastamyk2• 1 year ago

Yes, but won’t matter unless in a tight loop. I usually use % with logging but once in a while use f’’ if easier or needed for some reason.

jdranczewski• 1 year ago

I usually refer to https://pyformat.info/, which doesn't have all this detail, but most of the reasonable stuff is included

jvdvegt• 1 year ago

Why would "0^5" evaluate to 5? (question 21)

And is there a way to link to a specific question?

andrewfurey2003• 1 year ago

xor

palotasb• 1 year ago

^ is the XOR operator, 0 XOR 5 is 5. (Exponentiation is *)

https://docs.python.org/3/library/operator.html#mapping-oper...

teddyh• 1 year ago

Exponentiation is ** or pow()

procaryote• 1 year ago

One can question why python needs N built-in ways to printf with different syntax, different ways to escape things and different footguns.

6thbit• 1 year ago

“ There should be one-- and preferably only one --obvious way to do it.” — Zen of Python

pansa25• 1 year ago

many recent Python extensions seem features in search of use cases […] The real problem with Python, of course, is that its evolution is largely driven by narcissism, not user feedback.

Mark Lutz

https://learning-python.com/python-changes-2014-plus.html

lyu072822• 1 year ago

its evolution is largely driven by narcissism, not user feedback

Let's not psychoanalyze Guido

zahlman9• 1 year ago

why python needs N built-in ways to [do something where there should ideally be only one obvious way]

It's the same every time: because some people are unsatisfied with the existing ways and want new ones added, but other people will rain fire and brimstone if you remove the old ones.

(BTW: the exact — non-obvious — way the dashes are placed for that line of the Zen is apparently a deliberate joke.)

lillecarl3• 1 year ago

I really like the f"{ varname = }" syntax, didn't know about it before.

I have so much Python to learn, I scored 10/26

Ezhik2• 1 year ago

I learned a bunch of these when trying to make an f-string-like library for Lua [1], but `f"{...}" and the walrus ones caught me off-guard.

Glad this is nowhere near Wat [2], though.

[1] https://ezhik.jp/f-string.lua/

[2] https://www.destroyallsoftware.com/talks/wat

variadix• 1 year ago

That library looks awesome

Timwi3• 1 year ago

There are many mistakes in the Wat talk from destroyallsoftware. The biggest one is that he types `{}+[]` and claims that he's adding an object and a list. It's actually an empty scope followed by a unary + applied to a list. You can convince yourself of that by noting that `({}+[])` gives different output.

A smaller mistake that I find nonetheless amusing is that he uses Array(16) hoping to get 16 string separators. Oops, off by one error :)

Ezhik2• 1 year ago

Arguably that first one is just substituting one Wat for another.

travisgriggs• 1 year ago

Will there be a companion Tstrings.wtf at some point?

davepeck2• 1 year ago

Hah!

T-strings use the exact same syntax as f‑strings, but their “format spec” (the part after the optional :, like .2f) can effectively be anything.

That might make creating a quiz tricky? With f‑strings, Python immediately calls format() on that spec; with t‑strings, it's simply captured in Interpolation.format_spec. It's up to your code to decide whether to call format() or do something entirely different with this value.

tomrod• 1 year ago

Glorious. I learned a ton, and mostly more than the basics of formatting (something I've never spent a heap of time on). Well done.

Twey• 1 year ago

As someone who hasn't written Python in anger since before f-strings were a thing, I correctly guessed almost all the f-string specific syntax but made a bunch of errors that were just to do with the return values of various expressions. Maybe f-strings are the least wtf thing about Python? :)

pansa25• 1 year ago

Despite the URL, I’d only consider a few of these to be WTFs. Questions 20 & 21 definitely are, though:

  >>> a = 42
  >>> print(f"{a:=10}")
          42
  >>> print(f"{(a:=10)}")
  10

I still can’t believe anyone thought the walrus operator was a good idea.

almostgotcaught5• 1 year ago

this has nothing to do with the walrus operator and everything to do with how string.format works in python https://docs.python.org/3/library/string.html#format-string-...

Edit: someone downvoted me because they don't understand there is no walrus operator here

    print(f"{a:=10}")

lyu072822• 1 year ago

They obviously meant the second example:

     >>> print(f"{(a:=10)}")

sfink3• 1 year ago

You can pry the walrus operator from my cold dead hands.

    m = re.match(pattern1, line)
    if m:
        do_stuff(m.group(1))
    else:
        m = re.match(pattern2, line)
        if m:
            do_other_stuff(m.group(2))
        else:
            m = re.match(pattern3, line)
            if m:
                do_things(m.groups())
            else:
                m = ...

Obviously, there are ways to improve this particular example without using the walrus. But it's also usually not this simple.

I run into something like this all the time. Not many times per program, and I don't actually use the walrus all that often, but when it's the right thing it's so very nice.

marcosdumay• 1 year ago

You know, creating functions is allowed in Python. As are loops.

The assignment is the least problematic thing on that code. I do even disagree on it being a problem.

callc• 1 year ago

Even though I’ve never used python walrus, I’m a huge fan of the “X language feature can be used as an expression”

I feel the same way with rust control flow being used as an expression, and am disappointed when other languages don’t have it.

Even though one could argue it makes things more complicated, I feel more mental freedom and feel the language getting out of the way.

pansa25• 1 year ago

The walrus operator hardly changes that example at all:

    if m := re.match(pattern1, line):
        do_stuff(m.group(1))
    else:
        if m := re.match(pattern2, line):
            do_other_stuff(m.group(2))
        else:
            if m := re.match(pattern3, line):
                do_things(m.groups())
            else:
                m = ...

I've found `:=` useful in the headers of `while` loops, but that's about it. The complexity that walrus adds to the language far outweighs its usefulness.

Veedrac• 1 year ago

FWIW another way to handle this is a local function with early returns. In this example you can also just use a single regex and most likely win performance too.

:= is so common in other languages, or even other Python statements, that it doesn't bother me at all, but Python is such an imperative-first language that its presence is rarely felt.

jan_Sate• 1 year ago

Woah. That's tough. I scored 12/26.

I'm surprised to find that there're so many feature of f-string that I've never heard of. I don't think I'm gonna use them any time soon but nice to know about that.

noisy_boy• 1 year ago

16/26 I rarely code in python but thought I knew f-strings well - evidently I don't. I am still thinking in 3.6 mode.

ziml77• 1 year ago

I don't really think there's anything "wtf" worthy about this. A lot of it isn't even about f-string behavior but about the "mini-language" for str.format()

0cf8612b2e1e2• 1 year ago

There were a few wats in there, but I agree that most of the test was if you know all of the string formatting syntax.

recursivecaveat• 1 year ago

I got 20/26. Only ones that really got me were walrus syntax collisions, the types with weirder padding behaviour, some format specifiers I wasn't familiar with. A lot of these are more trivia than wtfs, but not a bad quiz.

cdaringe• 1 year ago

This is a nice analog to the JS WAT vid [1] of 2012

[1] https://www.destroyallsoftware.com/talks/wat

va1a2• 1 year ago

Fun video, you can really feel the 2012 in it too.

elternal_love• 1 year ago

Oh am I writing python code for some years this should be fun ... oh. Oh I see. Hmm. Ok, just give it to me: are they turing complete yet or do we need to wait for 3.14?

zahlman9• 1 year ago

They've been Turing-complete since they were introduced:

  $ py3.6
  >>> def arbitrary_code(): pass
  ... 
  >>> f"{exec('arbitrary_code()')}"
  'None'
  >>>

cvoss2• 1 year ago

I think the feature bloat here has passed the break-even point where no one person needs all this, and it takes so long to find what you need in the docs, and you can't be expected to memorize it, because it's so rare to need to use it, and you can't reliably reverse-search the esoteric syntax you encounter, that any given dev is going to take the path of least resistance and write their own routines for this stuff.

Pad left? That's a two-line method at most. Versus trying to remember whether the syntax is x:n< or x:<n or what. It's faster to do it yourself ad-hoc. And if the next dev has a question about how it works, the implementation is right there (and easy to customize!) not buried in the docs and immutable.

al_borland• 1 year ago

I find that weird stuff is often used a lot in a single code base, or it’s not used at all. Solve it once, and copy/paste it every other time you need it in the future.

dvdkon• 1 year ago

I'd take the middle road, provide a pad_left/pad_right function or method with keyword arguments for specifying things like the padding character. With how often I need to pad some string (often but not every day), this would be my favourite solution.

The standard library having no solution of its own is how you end up with JavaScript and every project reimplementing their 10% of a proper standard library, only slower and with more bugs.

Though I won't probably use Python's </>/^ format modifiers in my project, I could maybe see them working out in some software that frequently outputs "monospaced" text. In a particular niche, what we think of a needless character-pinching might be seen as a crucial feature and used daily.

zahlman9• 1 year ago

Pad left? That's a two-line method at most.

The functionality comes from the prior string.format method, which has been around since Python 2.6 (first released in 2008).

https://docs.python.org/2.6/library/string.html#formatspec

It's faster to do it yourself ad-hoc.

I have found the syntax to be quite mentally "sticky".

the implementation is right there (and easy to customize!) not buried in the docs and immutable.

There are hooks to customize it.

actinium226• 1 year ago

Oof, I got 14/26. I thought I knew f strings fairly well!

rossant• 1 year ago

15/26 despite nearly 20 years of Python. Should I be ashamed? (Granted, I’ve used it a bit less since f-strings became widespread)

jasonm23• 1 year ago

print(f"{f"{{}}"}") - Syntax error... eval it.

quotemstr• 1 year ago

Half of these are downstream of the design choice of using { instead of TypeScript-style ${ to delimit expressions.

Fstrings.wtf

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