1. Си / Говнокод #24517

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    // https://github.com/Qqwy/raii_with/blob/74e4c66a821fba6a483d62a8c583b3fab06e3443/raii/raii.h#L60

/**
 * Custom Control Structure Macro to provide Resource Acquisition Is Initialization (and Resource Relinquishment is Destruction).
 *
 * Use this to run a block of code with `var_decl` initialized to `init`, where at the end of the block (or at an earlier `safe_return`),
 * the passed `destr`-function will automatically be called with the given resource.
 *
 * Gotcha's:
 * 1. Do not use `return` from within `raii_with`, but only `safe_return`, because otherwise the destructors will not be run.
 * 2. Do not perform pointer-swaps with `var_decl`; the destructor will still be run on the original structure, because `raii` keeps its own reference to the resource.
 */
#define raii_with(var_decl, init, destr)                                \
  while(1) /* i.c.m. break on l.4, so we can jump past the user-supplied block */ \
    if(0)                                                               \
    raii_glue(__raii_with_finished, __LINE__):                              \
      break;                                                            \
    else                                                                \
      /* initialize _tmp lifetime list elem so replacement `raii_lifetime_list` can have previous one as tail. */ \
      for(struct raii_lifetime_list_t _tmp = {.elem.resource = init, .elem.destructor = destr, .next = raii_lifetime_list};;) \
        /* initialize user-supplied variable name */                    \
        for(var_decl = _tmp.elem.resource;;)                            \
          if (1) {                                                      \
            /* Fill `_tmp`'s tail before `raii_lifetime_list` is shadowed */ \
            _tmp.next = raii_lifetime_list;                             \
            goto raii_glue(__raii_with_setup, __LINE__);                    \
          } else                                                        \
          raii_glue(__raii_with_setup, __LINE__):                           \
            /* Shadow `raii_lifetime_list` with inner version */        \
            for(struct raii_lifetime_list_t *raii_lifetime_list = &_tmp;;) \
              if(1){                                                    \
                goto raii_glue(__raii_with_body, __LINE__);                 \
              } else                                                    \
                while (1) /* so break works as expected */              \
                  while (1) /*so continue works as expected */          \
                    if (1){                                             \
                      /*after the else-block (or break or continue), destruct and finish */ \
                      destruct_raii_lifetime(raii_lifetime_list->elem); \
                      goto raii_glue(__raii_with_finished, __LINE__);       \
                    } else                                              \
                    raii_glue(__raii_with_body, __LINE__):


#endif // RAII_WITH_H

    raii

    A simple library to provide RAII in standard-compliant C99, using raii_with(resource, initializer, destructor) { ... }-syntax:

    Запостил: j123123, 19 Июля 2018

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