/prog/ - C coroutines — Tinychan BBS

Name: Anonymous 2019-02-08 10:27

#ifndef COROUTINE_H
#define COROUTINE_H

#include <stdlib.h>

/*
 * `scr' macros for static coroutines.
 */

#define scrBegin         static int scrLine = 0; switch(scrLine) { case 0:;
#define scrFinish(z)     } return (z)
#define scrFinishV       } return

#define scrReturn(z)     \
        do {\
            scrLine=__LINE__;\
            return (z); case __LINE__:;\
        } while (0)
#define scrReturnV       \
        do {\
            scrLine=__LINE__;\
            return; case __LINE__:;\
        } while (0)

/*
 * `ccr' macros for re-entrant coroutines.
 */

#define ccrContParam     void **ccrParam

#define ccrBeginContext  struct ccrContextTag { int ccrLine
#define ccrEndContext(x) } *x = (struct ccrContextTag *)*ccrParam

#define ccrBegin(x)      if(!x) {x= *ccrParam=malloc(sizeof(*x)); x->ccrLine=0;}\
                         if (x) switch(x->ccrLine) { case 0:;
#define ccrFinish(z)     } free(*ccrParam); *ccrParam=0; return (z)
#define ccrFinishV       } free(*ccrParam); *ccrParam=0; return

#define ccrReturn(z)     \
        do {\
            ((struct ccrContextTag *)*ccrParam)->ccrLine=__LINE__;\
            return (z); case __LINE__:;\
        } while (0)
#define ccrReturnV       \
        do {\
            ((struct ccrContextTag *)*ccrParam)->ccrLine=__LINE__;\
            return; case __LINE__:;\
        } while (0)

#define ccrStop(z)       do{ free(*ccrParam); *ccrParam=0; return (z); }while(0)
#define ccrStopV         do{ free(*ccrParam); *ccrParam=0; return; }while(0)

#define ccrContext       void *
#define ccrAbort(ctx)    do { free (ctx); ctx = 0; } while (0)

#endif /* COROUTINE_H */

Name: Anonymous 2019-02-08 11:03

FREEZE MY ANUS

Name: Anonymous 2019-02-08 12:42

>>2
Source:
https://www.chiark.greenend.org.uk/~sgtatham/coroutines.html

Name: Anonymous 2019-02-08 13:28

>>3
he's cool. he has one other article about preprocessor metaprogramming: https://www.chiark.greenend.org.uk/~sgtatham/mp/

take notes FrozenAnus, that's how you do it in a readable/understandable way

Name: Anonymous 2019-02-09 12:36

Nice. TinyProg need more posts liek that.

Name: Anonymous 2019-02-09 15:54

>>5

Moar poasts

Name: Anonymous 2019-02-09 18:53

https://github.com/guillermocalvo/exceptions4c
http://libcello.org/

Name: Anonymous 2019-02-09 20:19

>>7
Coroutines are great and libcello looks fun.
But why would you want to bring the insanity of exceptions to a language that, despite its flaws, at least is not afflicted with them?

Name: Anonymous 2019-02-09 20:35

>>8
exceptions suck, but error-handling by return values in complex software sucks more. there are better ways but I guess bolting multiple returns, either types, option types or monadic errors onto C is harder than longjmp

Name: Anonymous 2019-02-09 21:29

>>9
setjmp?

Name: Anonymous 2019-02-09 23:30

#define dubs(n) n##n
#define claim(x) return (x)

#define postBegin int main() {
#define postFinish }

postBegin
    claim(dubs(1));
postFinish

Name: Anonymous 2019-02-10 11:38

You can now run and debug C in a browser.
https://vasyop.github.io/miniC-hosting/

Name: Anonymous 2019-02-10 20:00

>>9
Either types are monadic errors. Option types are isomorphic to Either Unit.

Name: Anonymous 2019-02-11 1:40

postBegin
    claim(dubs(12));
postFinish

hmm

Name: Anonymous 2019-02-11 7:00

>>13
wrong. either types can be monadic errors, but it is trivial to implement them in a way that doesn't conform to the definition of a monad. just a tagged union is enough to have either types. of course having them be a proper monad is good and makes error handling easier, but it is still possible to do it the other way.

Name: Anonymous 2019-02-13 14:02

This magic can't exist in D, because it has no preprocessors.
https://dlang.org/articles/pretod.html

Name: Anonymous 2019-02-14 16:02

I hate C preprocessor so much.

Name: Anonymous 2019-02-16 5:20

>>17
baka

C coroutines

1 Name: Anonymous 2019-02-08 10:27

2 Name: Anonymous 2019-02-08 11:03

3 Name: Anonymous 2019-02-08 12:42

4 Name: Anonymous 2019-02-08 13:28

5 Name: Anonymous 2019-02-09 12:36

6 Name: Anonymous 2019-02-09 15:54

7 Name: Anonymous 2019-02-09 18:53

8 Name: Anonymous 2019-02-09 20:19

9 Name: Anonymous 2019-02-09 20:35

10 Name: Anonymous 2019-02-09 21:29

11 Name: Anonymous 2019-02-09 23:30

12 Name: Anonymous 2019-02-10 11:38

13 Name: Anonymous 2019-02-10 20:00

14 Name: Anonymous 2019-02-11 1:40

15 Name: Anonymous 2019-02-11 7:00

16 Name: Anonymous 2019-02-13 14:02

17 Name: Anonymous 2019-02-14 16:02

18 Name: Anonymous 2019-02-16 5:20