Message349361
I have just read PEP 7 and noticed that its line-breaking recommandation in presence of binary operations seems to contradict its analogue in PEP 8 which follows Knuth's rule.
PEP 7 (https://www.python.org/dev/peps/pep-0007/#code-lay-out):
> When you break a long expression at a binary operator, the operator
> goes at the end of the previous line, and braces should be formatted
> as shown. E.g.:
>
> if (type->tp_dictoffset != 0 && base->tp_dictoffset == 0 &&
> type->tp_dictoffset == b_size &&
> (size_t)t_size == b_size + sizeof(PyObject *))
> {
> return 0; /* "Forgive" adding a __dict__ only */
> }
PEP 8 (https://www.python.org/dev/peps/pep-0008/#should-a-line-break-before-or-after-a-binary-operator):
> To solve this readability problem, mathematicians and their
> publishers follow the opposite convention. Donald Knuth explains the
> traditional rule in his Computers and Typesetting series: "Although
> formulas within a paragraph always break after binary operations and
> relations, displayed formulas always break before binary operations"
> [3].
>
> Following the tradition from mathematics usually results in more
> readable code:
>
> # Yes: easy to match operators with operands
> income = (gross_wages
> + taxable_interest
> + (dividends - qualified_dividends)
> - ira_deduction
> - student_loan_interest)
> In Python code, it is permissible to break before or after a binary
> operator, as long as the convention is consistent locally. For new
> code Knuth's style is suggested. |
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Date |
User |
Action |
Args |
2019-08-10 21:46:12 | maggyero | set | recipients:
+ maggyero, docs@python |
2019-08-10 21:46:12 | maggyero | set | messageid: <1565473572.7.0.81062665759.issue37813@roundup.psfhosted.org> |
2019-08-10 21:46:12 | maggyero | link | issue37813 messages |
2019-08-10 21:46:12 | maggyero | create | |
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