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1. Just Ellie 🐍 (noelle@chat.noelle.codes)'s status on Tuesday, 28-Jun-2022 13:49:30 UTC Just Ellie 🐍

   Is C++ still a strict superset of C? (I suppose it depends on which C you mean; I think C++ is based on ANSI C?)

   I ask because I saw someone refer to C++ as "just C with enhancements" and even if it is still a strict superset that seems a little silly.

   • asm & tamsyn & bytes, oh my! (millihertz@oldbytes.space)'s status on Tuesday, 28-Jun-2022 13:49:29 UTC asm & tamsyn & bytes, oh my!

     in reply to

     @noelle turns out i'm wrong: C++ never was a strict superset of C, and indeed C99 adopted some C++ stuff

     but, for example, K&R-style type declarations have never been valid C++, and nor has the idea of void* being a universal pointer type; and C++ is way stricter about function type signatures (which i guess is necessary to allow overloading)

     Santa Claes 🇸🇪🇭🇰🎅 likes this.
   • asm & tamsyn & bytes, oh my! (millihertz@oldbytes.space)'s status on Tuesday, 28-Jun-2022 13:49:30 UTC asm & tamsyn & bytes, oh my!

     in reply to

     @noelle no, i think they diverged at around the turn of the century

   • Santa Claes 🇸🇪🇭🇰🎅 (clacke@libranet.de)'s status on Wednesday, 29-Jun-2022 00:29:19 UTC Santa Claes 🇸🇪🇭🇰🎅

     in reply to

     • asm & tamsyn & bytes, oh my!
     @noelle @millihertz Yeah. The only way to make a language a superset of another language is to make sure that every syntax addition is a syntax error in the base language.
     
     C++ does not go out of its way to do that. Objective-C however is a different story!
     
     The funnest C/C++ programs are those that are valid in both, but do not mean the same thing.
   • Just Ellie 🐍 (noelle@chat.noelle.codes)'s status on Wednesday, 29-Jun-2022 00:29:20 UTC Just Ellie 🐍

     in reply to

     • asm & tamsyn & bytes, oh my!

     @millihertz Huh! When I learned C++ back in the distant, veiled past... well, hm. I thought I recalled the books I learned from all calling it a strict superset, but they may have hedged and just called it a superset, which allows for some divergences. (Indeed, as recently as 2012 - and possibly more recently than that - O'Reilly was claiming that "C++ is a superset of C. All your C programs will work without any modification in this environment."

     StackOverflow, on the other hand, has an entertaining counter-example: this is valid C but will definitely not compile under C++:

     int class = 1;
     int private = 2;
     int public = 3;
     int virtual = 4;