Code in question:
a = 'test'
# 1)
print(f'{a}') # test
# 2)
print(f'{ {a} }') # {'test'}
# 3)
print(f'{{ {a} }}') # {test}
My question is, why does case two print those quotes?
I didn't find anything explicitly in the documentation. The closest thing I found detailing this was in the PEP for this feature:
(the grammar for F-strings)
f ' <text> { <expression> <optional !s, !r, or !a> <optional : format specifier> } <text> ... '
The expression is then formatted using the format protocol, using the format specifier as an argument. The resulting value is used when building the value of the f-string.
I suppose that the value of a is being formatted with some formatter, which, since the data type is a string, wraps it with quotes. This result is then returned to the surrounding F-string formatting instance.
Is this hypothesis correct? Is there some other place which documents this more clearly?