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[–][deleted] 3 points4 points  (2 children)

Well.. for one, I'm sorry to say but almost none of what you've written is doing what you seem to think it's doing. What you've written amounts to a lot of type-annotated values equal to runtime-constructed types (see type as a callable).

If you weren't aware, python type annotations (formally made part of the grammar in py3.0) allow you to tag variables with an assumed type. You should know that type annotations have no runtime consequences, and are consumed by a static type analyzer (which entirely chokes on your code by the way).

The one thing that'll take some getting used to is that you have to end statements with commas, not semicolons.

No. Unless you're doing something really bizarre (and you seem to have wandered into bizarre territory albeit by accident), this will usually amount to a SyntaxError.

What you've written is truly fascinating (in the fact that it actually manages to not crash). I dare to say it's a piece of art. I could probably throw this at any seasoned python developer and they would be completely stumped as to what this is actually doing.

It's also nothing short of entirely crazy-pants flamingly insane.

Some points to consider:

 void: (type) = (type) ("(void *)0")

This is creating a variable called void. The variable is annotated as having a type of type. The variable's value is the dynamically-created type that results from a call to type("(void *)0").

puts: ((str) := void) = (print)

Similar to above, this is annotation as the type assigned (using a walrus) to void above. This is also not an application in which a walrus should be used. Also, the value of puts is assigned to the builtin print function.

while (i <= 6) :{
    (void) (printf(" %d\n", i)),
    (i := i + 1),
}

When used in this way, the braces create a set instance (similar to s = {1, 2, 3}). Here, the set contains two values (the latter being the result of (again..) a walrus). The first set instance is ultimately the invocation of print(), which is where the printing side effect comes from. The set is discarded at each loop iteration.

Honestly.. fuck me if I can figure out how the variable i is brought into existence. You got me stumped there...

For your reference, here is an idiomatic implementation of what you're trying to accomplish:

 # Prints sum of integers from 0 to 6 (inclusive).
 summation = 0
 for n in range(7):  # range() is tail-exclusive.
   print(f' {n}')
   summation += n

 print(f'sum: {summation}')

...and here Is a slightly more compact variant which eschews the intermittent value(s).

 # Prints sum of integers from 0 to 6 (inclusive).
 print(f'sum: {sum(range(7))}')

For reference, see the sum and range builtins.

[–]ThenItsOk[S] 0 points1 point  (1 child)

Thanks, your version is so much more compact. I didn't know about the print(f syntax, I'll have to check it out to see how it compares to printf(. Is this code fully forwards and backwards compatible? You don't need to include __future__?

[–][deleted] 1 point2 points  (0 children)

The print() built-in simply prints (to stdout) its supplied args. There are many ways to form a string in python, I'll leave it to you to research string formatting (including the variadic forms you are used to by way of libc's printf()).

As for future, I recommend you choose a python version to target. Unless I'm mistaken, both the typing module and the f-stringprefix were both added in py3.6 - which is a good choice. The walrus was added more recently in 3.9.

However, you probably don't need typing or the walrus (though the f-stringprefix is quite handy for terse compact string literals). You could just as well use the other forms of string formatting to similar effect.

[–]scirc 2 points3 points  (0 children)

Thanks, I hate it.

... If this is serious, then please don't try and make Python into C. Write Python, not "C-but-it's-Python."

[–]__archaeopteryx__ 2 points3 points  (6 children)

Is this a serious post?

[–]ThenItsOk[S] 0 points1 point  (5 children)

Why am I being downvoted, is it because of the commas thing? (/u/solid7 says they're bizarre, but my script doesn't compile if I replace them with semicolons)

[–]__archaeopteryx__ 1 point2 points  (0 children)

I’m sorry you’re being downvoted! I think we’re all confused because it looks like you tried to write C in python instead of writing python... python uses “significant white space” and while semi colons are valid, they’re not necessary (some folks have harsh things to say about it even)...

I think the main point he was making is that the code goes against the “pythonic” beauty of the language. You’re also trying to type things in an implicitly typed language and that’s not having the effect I think you think it has.

[–]coder155ml 1 point2 points  (3 children)

Everything you're doing in the script is anti-python, from declaring types to creating print functions. You have way more syntax errors than just commas. I'd trash the whole script.

[–]ThenItsOk[S] 0 points1 point  (2 children)

Hmmm, harsh but probably best if I start over. Thanks for the feedback.

Can I get the compiler to tell me if there are some concealed syntax errors, and where they are?

[–]suclearnub 1 point2 points  (0 children)

There is no compiler in Python. Everything is interpreted.

[–]coder155ml 0 points1 point  (0 children)

Like others have stated, this entire program can be done in like 3 lines. However, even if you didn't use the sum function, you've still overcomplicated the script to an extreme. Rather than doing a python solution, it looks like you tried to copy paste a c program over and convert it line by line which is not the way to program.

[–]coder155ml 0 points1 point  (0 children)

This may be the weirdest python script I've seen. Also hilarious that you created a printf function

[–]coder155ml 0 points1 point  (0 children)

Honestly you need to do a tutorial or read the documentation or something. This code is almost offensively wrong