python断句 python断行

包装长行的首选方法是在括号,括号和括号内使用Python隐含的行继续.通过在括号中包装表达式,可以在多行中分割长行.这些应该优先使用反斜杠来继续行.

反斜杠有时可能仍然合适.例如,long,多个with语句不能使用隐式延续,因此可以接受反斜杠:

with open('/path/to/some/file/you/want/to/read') as file_1, \
open('/path/to/some/file/being/written', 'w') as file_2:
file_2.write(file_1.read())

另一个这样的情况是断言语句.

确保适当缩进续行.打破二元运算符的首选位置是运算符之后,而不是它之前.一些例子:

class Rectangle(Blob):
def __init__(self, width, height,
color='black', emphasis=None, highlight=0):
if (width == 0 and height == 0 and
color == 'red' and emphasis == 'strong' or
highlight > 100):
raise ValueError("sorry, you lose")
if width == 0 and height == 0 and (color == 'red' or
emphasis is None):
raise ValueError("I don't think so -- values are %s, %s" %
(width, height))
Blob.__init__(self, width, height,
color, emphasis, highlight)