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Comment by Bigpet | Hacker News Reader

Fully agree with #embed. I don't really need the feature often enough to justify it. But it feels fine to use the preprocessor for it. It's annoying enough for the people who need it to have some build-system work-around, so just some simple straight forward implementation seems better than some over-specified solution for every possible use-case (imagine the horror of some template construct with locales/encoding specification added to it). Also, even if C keeps diverging from C++ having these basic constructs stay compatible is worth quite a lot imho.

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One problem is that C++ wants to (eventually, at least as an ambition) deprecate the pre-processor. So it's embarrassing to add features which people need to this system which you claim you're deprecating. Which is it?

I think C++ would have been better off with a closer equivalent to include_bytes! (Rust's compiler intrinsic masquerading as a macro, which gives back an immutable reference to an array with your data in it) - but the C++ language doesn't really have a way to easily do that, and you can imagine wrestling with a mechanism to do that might miss C++ 26, which is really embarrassing when this is a feature your language ought to have had from the outset. So settling on #embed for C++ 26 means it's done.

I was concerned that maybe include_bytes! prevents the compiler from realising it doesn't need this data at runtime (e.g. you include_bytes! some data but just to calculate a compile time constant checksum from it) but nope, the compiler can see it doesn't need the array at runtime and remove it from the final binary just as a C++ compiler would with #embed.

> having these basic constructs stay compatible is worth quite a lot

Also, I think C++ can still use the same preprocessor as C at this point (it's been a while since I've had to deal with that)? If you're going to diverge the preprocessor you should get more benefit out of doing so than "not having #embed". For that matter, having important features like #embed only available via preprocessor also helps undermine the pointy-haired trolls who (allegedly?) keep trying to deprecate the preprocessor entirely in favor of some proprietary build system.

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