Macros on Steroids: How pure C can benefit from metaprogramming

Post by mumblemumble » Thu, Jul 22, 2021, 8:46 PM UTC

spaetzleesser wrote: post #41

gsmecher wrote: post #12

Earlier quoted context omitted.

To date, C's most proximate (management-friendly, technically similar, programmer-skill-adjacent) competition has been c++. (I'm trying to lay the groundwork for the next statement: I'm not claiming this is good, and excited to see Rust and friends as serious contenders. Stay with me.) Even in c++20, there are things you can do with macros you can't do in the language. This may change when reflection lands in c++2x,…

When I look at a lot of things that are done with reflection in C# I personally would much prefer the preprocessor and macros. Things that could be done in a type safe manner with a macro in a few lines become way more complex when using reflection.

Post by Banana699 » Thu, Jul 22, 2021, 9:01 PM UTC

Hirrolot wrote: post #21

IncRnd wrote: post #20

You could create this as a frontend macro preprocessor that implements new language constructs. Maybe it could be called cfront. I just hope that the usefulness of that doesn't lead to bloated and complex codebases and binaries as features are added to the preprocessor.

There are several reasons why not to resort to third-party code generators [1]. This includes the burden of maintenance (think about the build process) and seamless integration of native macros with other code. Do you have some code to show bloated binaries with Datatype99/Interface99? The last time I checked the generated assembly code, it was nearly of the same size as hand-written code [2]. [1]: https://github.com…

Post by touisteur » Thu, Jul 22, 2021, 9:03 PM UTC

spaetzleesser wrote: post #41

gsmecher wrote: post #12

Earlier quoted context omitted.

To date, C's most proximate (management-friendly, technically similar, programmer-skill-adjacent) competition has been c++. (I'm trying to lay the groundwork for the next statement: I'm not claiming this is good, and excited to see Rust and friends as serious contenders. Stay with me.) Even in c++20, there are things you can do with macros you can't do in the language. This may change when reflection lands in c++2x,…

When I look at a lot of things that are done with reflection in C# I personally would much prefer the preprocessor and macros. Things that could be done in a type safe manner with a macro in a few lines become way more complex when using reflection.

Post by touisteur » Thu, Jul 22, 2021, 9:44 PM UTC

WalterBright wrote: post #45

touisteur wrote: post #43

Earlier quoted context omitted.

I'm curious of your opinion about AdaCore CCG, an SPARK to C compiler, for targets that don't have an Ada compiler yet.

I do not know enough about them to have a worthwhile opinion.

Post by spaetzleesser » Fri, Jul 23, 2021, 2:08 AM UTC

mumblemumble wrote: post #42

spaetzleesser wrote: post #41

Earlier quoted context omitted.

When I look at a lot of things that are done with reflection in C# I personally would much prefer the preprocessor and macros. Things that could be done in a type safe manner with a macro in a few lines become way more complex when using reflection.

Could I beg of you to give an example? Back when I was working in C#, there were quite a few times when I'd encounter things being done with reflection that I wish had been done with less code and a more type safe manner by just... not using reflection. I always just assumed a lot of that was just bad habits left over from the .NET 1.0 days, back before generics. So I'm curious if there's much overlap there? If it's…

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