- fprintf (stderr, "%s: ", program_name);
- if (problem == -1)
- fprintf (stderr, "invalid");
- else /* Assume -2. */
- fprintf (stderr, "ambiguous");
- fprintf (stderr, " %s `%s'\n", kind, value);
+ const char *fmt = (problem == -1
+ ? "%s: invalid %s `%s'\n"
+ : "%s: ambiguous %s `%s'\n");
+ fprintf (stderr, fmt, program_name, kind, value);