PEP 8 does not seem to prescribe whether line breaking should start from the beginning or from the end of the line, in order to stay within the 79 character limit.
For instance where should I break this line?
long_function_name_1(long_function_name_2(long_function_name_3(long_function_name_4(long_function_name_5(long_function_name_6(long_function_name_7(long_function_name_8(args))))))))
From the beginning?
long_function_name_1(
long_function_name_2(
long_function_name_3(
long_function_name_4(
long_function_name_5(
long_function_name_6(
long_function_name_7(long_function_name_8(args))))))))
Or from the end?
long_function_name_1(long_function_name_2(long_function_name_3(
long_function_name_4(long_function_name_5(long_function_name_6(
long_function_name_7(long_function_name_8(args))))))))
I am particularly interested in the rationale behind the recommendation of one form over the other.
I go with the beginning
long_function_name_1(
long_function_name_2(
long_function_name_3(
long_function_name_4(args))))
Indentation makes it clear what function accepts what. If there is more than one argument then they'll form a 'column' (in that case would be better to move the ending parenthesis to a new line too).