在Python中使用双引号而不是单引号打印空字符串

Question

I have a list I want to pretty print that contains empty lists as well as lists with string members. the problem is that lists that contains strings are printed with double quotes:

>>>str(['a'])
"['a']"

But an empty list is printed with single quotes:

>>> str([])
'[]'

Is there a way to always force printing string with double quotes ?

Answer 1

It depends on the representation of the object being printed; if the string to print contains the \\" character, then a single quote will be used; if the string contains the \\' character, then a double quote will be used.

Answer 2

Use custom string formatting:

print '"{}"'.format(str([]))

prints

"[]"

This won't affect strings nested in containers, though:

print '"{}"'.format(str(["a"]))

prints

"['a']"