What PEP 8 guidelines do you ignore, and which ones do you stick to? [closed]

Answer 1

My "admit violation" is about "if"

PEP8 says no multiple statement in one line, so for if we must do this :

if cond:
    actions
    ...

But when there only one action, I prefer all in one line, e.g. I prefer :

if a == 0: b = 0

than:

if a == 0:
     b = 0

Answer 2

PEP 8 says:

Yes:

x = 1
y = 2
long_variable = 3

No:

x             = 1
y             = 2
long_variable = 3

i usually follow it, but i sometimes use another variant, for the sake of better readability:

x =             1
y =             2
long_variable = 3

Answer 3

When I'm writing tiny scripts I often just use two spaces.

I always use the same pattern for docstrings:

def function():
    """
    Even if it's a single line.
    """

Answer 4

python-mode.el, https://launchpad.net/python-mode

meanwhile allows customization of style:

M-x customize-variable RET py-docstring-style RET

Default value is pep-257-nn

Implemented styles are DJANGO, ONETWO, PEP-257, PEP-257-NN, SYMMETRIC, and NIL.

A value of NIL won't care about quotes position and will treat docstrings a normal string, any other value may result in one of the following docstring styles:

DJANGO:

"""
Process foo, return bar.
"""

"""
Process foo, return bar.

If processing fails throw ProcessingError.
"""

ONETWO:

"""Process foo, return bar."""

"""
Process foo, return bar.

If processing fails throw ProcessingError.

"""

PEP-257:

"""Process foo, return bar."""

"""Process foo, return bar.

If processing fails throw ProcessingError.

"""

PEP-257-NN:

"""Process foo, return bar."""

"""Process foo, return bar.

If processing fails throw ProcessingError.
"""

SYMMETRIC:

"""Process foo, return bar."""

"""
Process foo, return bar.

If processing fails throw ProcessingError.
"""

Answer 5

Standards are critical and PEP 8 is a very good style guide that I insist on. The only guideline I disagree with is the spacing around mathematical operators. For example PEP8 insists on the following spacings

Without PEP8                           With PEP8                
---------------------------------------------------------------- 
y = sqrt(x**2 + y**2)                  y = sqrt(x ** 2 + y ** 2) 
a*x**3 + b*x**2 + c*x + d              a * x ** 3 + b * x ** 2 + c * x + d 
10**(a*x + b)                          10 ** (a * x + b)  
F = V/(sqrt(g*h) + epsilon)            F = V / (sqrt(g * h) + epsilon) 
a*cos(nx/pi) + b*sin(nx/pi)            a * cos(nx / pi) + b * sin(nx / pi) 

I am trying to conform, but this is the one area where I am struggling. Do anyone else also feel that PEP8 spacing makes mathematics harder to read?

Update:

PEP8 was corrected to recommend the formatting on the left while discouraging the formatting on the right:

Yes:

i = i + 1
submitted += 1
x = x*2 - 1
hypot2 = x*x + y*y
c = (a+b) * (a-b)

No:

i=i+1
submitted +=1
x = x * 2 - 1
hypot2 = x * x + y * y
c = (a + b) * (a - b)

Answer 6

Multi-line conditionals etc.: PEP-8 explicitly says to break after a binary operator instead of before it. I'm afraid that I cannot see the appeal of that. It makes a lot more sense to me to break before the conditional, so that in wrapped/continued lines, each sub-line begins with the conditional:

if (condition1 \
        or condition2 \
        or condition3):
    do_something()

As can be seen, I also like to add an extra indent for the sublines, so that they are visually offset from the block below. PEP-8 does not say anything explicit about this (does it?), but the examples have the sub-lines lining up with the opening parentheses.