Re:Python's new t-strings
by 0cf8612b2e1e on Monday April 21, 2025 @12:12PM
(#43753590)
Linters will even complain if you have a f string without variables. I assume it will be the same for t strings.
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For the reasons discussed above, I'm not sure that it will be the case for t-strings. I think it'll take a little while for frameworks/libraries to adapt (while still maintaining backward compatibility) and a while for best practices to find their way into our linting and other tools.
Re:Python's new t-strings
by 0cf8612b2e1e on Monday April 21, 2025 @04:22PM
(#43756057)
If you can use a string anywhere you can use a t-string, then a non parametrized t-string is a code smell (lining error). If there is a dedicated template-string API, then there is the implicit threat you are breaking backwards compatibility to stop using regular strings.
> If you can use a string anywhere you can use a t-string
You can't; they're different types. t-strings are not `str`
It's up to good framework/API design to take advantage of this.
Re:Python's new t-strings
by 0cf8612b2e1e on Monday April 21, 2025 @05:43PM
(#43756834)
A library writer ultimately has to decide if they accept both types. For a database cursor, do you take regular strings + parameter arguments and template strings? Or dedicate a new API to the idea?
cursor.execute(“select * from x where foo=?”, {foo=1})
# while also allowing
cursor.execute(t“select * from x where foo={foo}”)
#Vs
cursor.executetemplate(“select * from x where foo={foo}”)
If ‘execute’ takes string and t-string, then I would consider it a problem to use a t-string without parameters. If there is a novel API just for t-strings, then you are implying widespread breaking changes as you have a schism between the two ways of providing parameters.My point was that library authors will need to consider this carefully. If you're writing a library where injection attacks matter, then -- long term -- you almost certainly do not want a single method that accepts `Union[str, Template]`. You probably either want to avoid accepting `str` entirely, or perhaps provide two separate methods. Some period of deprecation seems inevitable.
Re:Python's new t-strings
by WorldMaker on Monday April 21, 2025 @05:16PM
(#43756583)
Yeah, "t-string" is possibly a misnomer, because they are in fact at runtime a Template object (from string.templatelib).