Python解析空字符串

Question

I'm using the parse library and ran into surprising (to me) functionality: it does not match empty strings:

>>> from parse import parse
>>> parse('hi "{}"', 'hi "everybody"')
<Result ('everybody',) {}>
>>> parse('hi "{}"', 'hi ""')
>>> 

Is there a way, using parse , to get it to match any string between "" in the same way that re does:

>>> from re import match
>>> match('hi "(.*)"', 'hi "everybody"').groups()
('everybody',)
>>> match('hi "(.*)"', 'hi ""').groups()
('',)

Answer 1

Use a custom type conversion:

from parse import parse
def zero_or_more_string(text):
    return text

zero_or_more_string.pattern = r".*"
parse('hi "{:z}"', 'hi ""', { "z": zero_or_more_string })

and you'll get this:

<Result ('',) {}>