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Python’s new t-strings

(davepeck.org)
620 points tambourine_man | 1 comments | 21 Apr 25 04:31 UTC | HN request time: 0.204s | source
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serbuvlad ◴[21 Apr 25 09:51 UTC] No.43750075[source]▶
All things considered, this is pretty cool. Basically, this replaces

    db.execute("QUERY WHERE name = ?", (name,))
with

    db.execute(t"QUERY WHERE name = {name}")
Does the benefit from this syntactic sugar outweigh the added complexity of a new language feature? I think it does in this case for two reasons:

1. Allowing library developers to do whatever they want with {} expansions is a good thing, and will probably spawn some good uses.

2. Generalizing template syntax across a language, so that all libraries solve this problem in the same way, is probably a good thing.

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pinoy420 ◴[21 Apr 25 10:17 UTC] No.43750226[source]▶
Now instead of being explicit all it takes is someone unfamiliar with t strings (which will be almost everyone - still few know about f strings and their formatting capabilities) to use an f instead and you are in for a bad time.
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mcintyre1994 ◴[21 Apr 25 10:36 UTC] No.43750323[source]▶
Any sane library will just error when you pass a string to a function that expects a template though. And that library will have types too so your IDE tells you before you get that far.
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_Algernon_ ◴[21 Apr 25 15:59 UTC] No.43753438[source]▶
This would break backwardcompatibility pretty hard. In many cases it may not be worth it.
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1. hombre_fatal ◴[21 Apr 25 17:51 UTC] No.43754551[source]▶
Javascript already has prior art here.

A library can extend an existing database library like 'pg' so that PgClient#query() and PgPool#query() require string template statements.

That way 'pg' can continue working with strings, and people who want nice templated strings can use the small extension library, and the small extension library makes it impossible to accidentally pass strings into the query functions.