I've written `"text {foo}".format(foo=foo)` so many times I've almost convinced myself that it's not that verbose. Then i discovered fstrings introduced ins 3.6:
```
>>> f"text {fpp}"
'text foo'
```
>>> mind == blown
True
Python f-strings are the best syntax sugar i never knew about
1–10 of 14 posts
Re: Python f-strings are the best syntax sugar i never knew about
#2Thanks! I didn't know I had literal string interpolation available until today!
Re: Python f-strings are the best syntax sugar i never knew about
#3Ah yes, the thing we had in shell, Perl, and Ruby since forever, and that was
never a very good idea.
Re: Python f-strings are the best syntax sugar i never knew about
#4You can do cool nested calls with them too.
>>> class A:
... def __init__(self):
... self.foo = 5
... def bar(self):
... return 'cake'
...
>>> a = A()
>>> f'{a.foo}'
'5'
>>> f'{a.bar()}'
'cake'
>>> x = {'b': 1, 'c': 2}
>>> f"{x['b']}"
'1'Re: Python f-strings are the best syntax sugar i never knew about
#5it is very very true. F-strings are awesome.
But there is one use case that I prefer .format(), and is when formatting a string using a dictionary. Being able to is awesome:
some_long_string_template.format(**some_dictionary_with_many_keys)
Re: Python f-strings are the best syntax sugar i never knew about
#6Templated strings are great for when, as the name suggests, you want to create a string with some placeholders to be expanded at a later time.
When you just want to interpolate a string on the fly, Fstrings are absolutely the right thing to do most of the time.
Re: Python f-strings are the best syntax sugar i never knew about
#7You can do cool nested calls with them too. >>> class A: ... def __init__(self): ... self.foo = 5 ... def bar(self): ... return 'cake' ... >>> a = A() >>> f'{a.foo}' '5' >>> f'{a.bar()}' 'cake' >>> x = {'b': 1, 'c': 2} >>> f"{x['b']}" '1'
Interesting. Thanks for the post. I always just concatenated them out of laziness, and this looks even lazier.
Re: Python f-strings are the best syntax sugar i never knew about
#8You can do cool nested calls with them too. >>> class A: ... def __init__(self): ... self.foo = 5 ... def bar(self): ... return 'cake' ... >>> a = A() >>> f'{a.foo}' '5' >>> f'{a.bar()}' 'cake' >>> x = {'b': 1, 'c': 2} >>> f"{x['b']}" '1'
Interesting. Thanks for the post. I always just concatenated them out of laziness, and this looks even lazier.
It's super nice when you're working on reporting software: software that needs to quickly shoot out a string like this from time-to-time!
It's much nicer to write this:
f"{account_name} {pretty_date(start_date)} - {pretty_date(end_date)} account attribution"
and MUCH easier to maintain than the alternative...!
Re: Python f-strings are the best syntax sugar i never knew about
#9Ah yes, the thing we had in shell, Perl, and Ruby since forever, and that was never a very good idea.
Why wasn't it a good idea in these languages?
Re: Python f-strings are the best syntax sugar i never knew about
#10Templated strings are great for when, as the name suggests, you want to create a string with some placeholders to be expanded at a later time. When you just want to interpolate a string on the fly, Fstrings are absolutely the right thing to do most of the time.
true but it seems that the performance gap is pretty huge and the new f-strings actually come in on top for string substitution: