Elliptical Python Programming(susam.net)
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Elliptical Python Programming
https://susam.net/elliptical-python-programming.html
24 comments
Expanding on this a little, I will be replacing all occurrences of 2 with two blobs fighting, with shields:
>>> 0^((...==...)--++--(...==...))^0
2Numpy actively uses … to make slicing multidimensional arrays less verbose. There are also uses in FastAPI along the lines of «go with the default».
excellent explanation, to add to this since I was curious about the composition, '%c' is an integer presentation type that tells python to format numbers as their corresponding unicode characters[1] so
'%c' * (length_of_string_to_format) % (number, number, ..., length_of_string_to_format_numbers_later)
is the expression being evaluated here after you collapse all of the 1s + math formatting each number in the tuple as a unicode char for each '%c' escape in the string corresponding to its place in the tuple.
[1] https://docs.python.org/3/library/string.html#format-specifi...
'%c' * (length_of_string_to_format) % (number, number, ..., length_of_string_to_format_numbers_later)
is the expression being evaluated here after you collapse all of the 1s + math formatting each number in the tuple as a unicode char for each '%c' escape in the string corresponding to its place in the tuple.
[1] https://docs.python.org/3/library/string.html#format-specifi...
You can do this on JavaScript too.
alert(1)
// equals to:
[][(![]+[])[+!+[]]+(!![]+[])[+[]]][([][(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[][(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+([][[]]+[])[+!+[]]+(![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[])[+!+[]]+([][[]]+[])[+[]]+([][(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+[]]+(!![]+[][(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[+[]]]+(!![]+[])[+!+[]]]((![]+[])[+!+[]]+(![]+[])[!+[]+!+[]]+(!![]+[])[!+[]+!+[]+!+[]]+(!![]+[])[+!+[]]+(!![]+[])[+[]]+([][(![]+[])[+!+[]]+(!![]+[])[+[]]]+[])[+!+[]+[+!+[]]]+[+!+[]]+([]+[]+[][(![]+[])[+!+[]]+(!![]+[])[+[]]])[+!+[]+[!+[]+!+[]]])()
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This behavior can be replicated with any class that has two special methods:
__neg__ that returns -1 and __sub__ that accepts ints and returns 1-other.
For example if you make this class:
For example if you make this class:
class _:
def __neg__(self):
return -1
def __sub__(self, other):
return 1-other
>>> --_()
1
>>> _()--_()
2
I think we're really starting to over crowd pythons syntax and I'm not a fan.
TIL that in python, 1--2==3
It's not a python thing.
1-(-2), distribute the negative.
In most C-like languages that would be a syntax error. E.g. in C and C++ as a rule you tokenize "greedily", "1--2" would be tokenized as "1", "unary decrement operator", "2", which is illegal because you're trying to decerment an rvalue.
Python doesn't have "--", which allows the tokenizer to do something else.
Python doesn't have "--", which allows the tokenizer to do something else.
In C, that is really because Unary minus (negation) has precedence over binary operations.
I am pretty sure the decriment operator came around well after that quirk was established.
+a - b; // equivalent to (+a) - b, NOT +(a - b)
-c + d; // equivalent to (-c) + d, NOT -(c + d)
+-e; // equivalent to +(-e), the unary + is a no-op if “e” is a built-in type
// because any possible promotion is performed during negation already
I am pretty sure the decriment operator came around well after that quirk was established.
Peter van der Linden’s book “Expert C Programming” (which is awesome btw) says that one of them (Kernighan, Richie or maybe Ken Thompson I forget) realised early on that the c compiler had the wrong operator precedence for bit twiddling and unary and boolean operators but “at that stage we had a few thousand lines of C code and thought it would be too disruptive to change it”
Also worth noting that `1 - -2` works and produces 3 in C because the space breaks the operator.
If you're curious, the code in ellipsis results in executing:
print('hello, world')Thank you!
I noticed some ** and * in the thing sent to eval(), which (given that the building blocks are small integers) seemed related to prime factorizations.
The initial %c is duplicated 21 times (3*7, if I read correctly), and then string-interpolated (%c%c%c...) against a long tuple of integers. These integers themselves are composed of products of factors combined using * and **.
There is also one tuple "multiplication" embedded within that long tuple of integers -- (a,b)*2 = (a,b,a,b). That is for the 'l' 'l' in "hello".
It's all very clever and amusingly mathy, with a winking allusion to the construction of natural numbers using sets. It made me Godel.
I noticed some ** and * in the thing sent to eval(), which (given that the building blocks are small integers) seemed related to prime factorizations.
The initial %c is duplicated 21 times (3*7, if I read correctly), and then string-interpolated (%c%c%c...) against a long tuple of integers. These integers themselves are composed of products of factors combined using * and **.
There is also one tuple "multiplication" embedded within that long tuple of integers -- (a,b)*2 = (a,b,a,b). That is for the 'l' 'l' in "hello".
It's all very clever and amusingly mathy, with a winking allusion to the construction of natural numbers using sets. It made me Godel.
`--(...==...)--(...==...)` evaluates to `2` because the first block evaluates to 1, as previously mentioned, and then the next `-` is interpreted as an infix subtraction operator. The second `-(...==...)` evaluates to `-1`, so you get `1 - -1` or `2`.
When chaining multiple together, you can leave off the initial `--`, because booleans will be implicitly converted to integers if inserted into an arithmetic expression, e.g. `True - -1` -> `1 - -1` -> `2`.
> There should be one-- and preferably only one --obvious way to do it.
This article is obviously completely tongue-in-cheek, but I feel the need to point out that this sentence is not meant to be a complete inversion of the Perl philosophy of TIMTOWTDI. The word "obvious" is crucial here - there can be more than one way, but ideally only one of the ways is obvious.