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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: 0.21s | source
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avereveard ◴[21 Apr 25 07:14 UTC] No.43749173[source]▶
what's the tldr difference between this and .format ?
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OJFord ◴[21 Apr 25 09:41 UTC] No.43750013[source]▶
f-strings are syntactic sugar for .format, e.g.:

    f"foo is {foo} and {bar=}"
    "foo is {} and bar={}".format(foo, bar)
are equivalent.

t-strings are actually not strings, but Template objects, giving access to both the templating string and the parameters for processing. Sibling comments describe it as a custom .format implementation in that sense - it's f-string-like sugar where you're also allowed to take control of the .format function that it's sugar for.

replies(1): >>43757322 #
1. zahlman ◴[21 Apr 25 22:45 UTC] No.43757322[source]▶
f-strings are actually translated into formatting and concatenation of the pieces at a bytecode level; they don't call `.format` under the hood and thus aren't what I'd call "syntactic sugar" in the traditional sense. But yes, the equivalence holds.

t-strings, of course, (will) translate at the bytecode level into instantiation of the Template object (and whatever code is needed to compute the Interpolation values in-place).