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mananaysiempreyesterday at 1:45 PM1 replyview on HN

In theory, for straight-line code only, the If Statement Ladder of Doom is an alternative:

  int ret;
  FILE *fp;
  if ((fp = fopen("hello.txt", "w")) == NULL) {
      perror("fopen");
      ret = -1;
  } else {
      const char message[] = "hello world\n";
      if (fwrite(message, 1, sizeof message - 1, fp) != sizeof message - 1) {
          perror("fwrite");
          ret = -1;
      } else {
          ret = 0;
      }
  
      /* fallible cleanup is unpleasant: */
      if (fclose(fp) < 0) {
          perror("fclose");
          ret = -1;
      }   
  }
  return ret;
It is in particular universal in Microsoft documentation (but notably not actual Microsoft code; e.g. https://github.com/dotnet/runtime has plenty of cleanup gotos).

In practice, well, the “of doom” part applies: two fallible functions on the main path is (I think) about as many as you can use it for and still have the code look reasonable. A well-known unreasonable example is the official usage sample for IFileDialog: https://learn.microsoft.com/en-us/windows/win32/shell/common....


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