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Interviewer: Mr. Musk, I understand the wheels fell off the Cybertruck. Musk: Well, that’s not very typical. Most vehicles are designed so the wheels don’t fall off. Interviewer: B…

The binary bloat is also caused by unnecessary inlining and the linker eliminates most of it (but it's still annoying e.g. for godbolt). {fmt} supports a superset of std::format an…

std::print author here. Indeed, std::print shouldn't be expensive to compile, it's just a thin wrapper around a single type-erased function. The only reason why it is expensive in …

Modules have been working reasonably well in clang for a while now but MSVC support is indeed buggy.

This style is used in {fmt} and is great for documentation, especially on smaller screens: https://fmt.dev/12.0/api/#format_to_n

We did see build time improvements from deploying modules at Meta.

The main effect of this is that some of the conversions between char and char8_t are inefficient.

I was impressed how fast the Rust folks adopted this! Kudos to David Tolnay and others.

Note that ~3-6ns is on modern desktop CPUs where extra few kB matter less. On microcontrollers it will be larger in absolute terms but I would expect the relative difference to als…

I don't have exact numbers but from measuring perf changes per commit it seemed that most improvements came from "printing" (e.g. switching to BCD and SIMD, branchless exponent out…

If you compress the table (see my earlier comment) and use plain Schubfach then you can get really small binary size and decent perf. IIRC Dragonbox with the compressed table was ~…

It is possible to compress the table using the technique from Dragonbox ( https://github.com/fmtlib/fmt/blob/8b8fccdad40decf68687ec038... ) at the cost of some perf. It's on my TOD…

Note that it has the same table of powers of 10: https://github.com/rsc/fpfmt/blob/main/bench/uscalec/pow10.h

Somewhat notable is that `char8_t` is banned with very reasonable motivation that applies to most codebases: > Use char and unprefixed character literals. Non-UTF-8 encodings are r…

The shortest double-to-string algorithm is basically Schubfach or, rather, it's variation Tejú Jaguá with digit output from Dragonbox. Schubfach is a beautiful algorithm: I impleme…

Other examples are CTRE ( https://github.com/hanickadot/compile-time-regular-expressio... ) and format string compilation ( https://fmt.dev/12.0/api/#compile-api ). The closest C c…

It's easier to write faster code in a language with compile-time facilities such as C++ or Rust than in C. For example, doing this sort of platform-specific optimization in C is a …

Please note that there is some error in your port: Error: roundtrip fail 4.9406564584124654e-324 -> '5.e-309' -> 4.9999999999999995e-309 Error: roundtrip fail 6.6302941479442929e-3…

Yeah, that's what I meant.