88c88
< Print numbers from FIRST to LAST, in steps of INCREMENT.\n\
---
> Print numbers or characters from FIRST to LAST, in steps of INCREMENT.\n\
98,102c98,102
< If FIRST or INCREMENT is omitted, it defaults to 1.\n\
< FIRST, INCREMENT, and LAST are interpreted as floating point values.\n\
< INCREMENT should be positive if FIRST is smaller than LAST, and negative\n\
< otherwise.  When given, the FORMAT argument must contain exactly one of\n\
< the printf-style, floating point output formats %e, %f, %g\n\
---
> If FIRST is omitted, it defaults to 1 or a, if INCREMENT is omitted,\n\
> it defaults to 1. FIRST, INCREMENT, and LAST are interpreted as floating\n\
> point values. INCREMENT should be positive if FIRST is smaller than LAST,\n\
> and negative otherwise.  When given, the FORMAT argument must contain exactly\n\
> one of the printf-style, floating point output formats %e, %f, %g\n\
427,441c427,504
<   last = scan_double_arg (argv[optind++]);
<
<   if (optind < argc)
<     {
<       first = last;
<       last = scan_double_arg (argv[optind++]);
<
<       if (optind < argc)
<       {
<         step = last;
<         step_is_set = 1;
<         last = scan_double_arg (argv[optind++]);
<
<       }
<     }
---
>   /* Check if the user wants a character sequence or a numeric
>        sequence.
>   */
>   if( isalpha (argv[optind][0]) )
>         {
>                 char first;
>                 long int step;
>                 char last;
>
>                 switch (argc-optind)
>                         {
>                         case 1:
>                                 first = isupper( *argv[optind] )?'A':'a';
>                                 last = *argv[optind];
>                                 step = 1;
>                                 break;
>
>                         case 2:
>                                 first = *argv[optind];
>                                 last = *argv[optind+1];
>                                 step = last>first?1:-1;
>                                 break;
>
>                         case 3:
>                                 first = *argv[optind];
>                                 errno=0;
>                                 step = strtol (argv[optind+1], 0, 10);
>                                 last = *argv[optind+2];
>                                 break;
>                         }
>
>                 if (errno || !step)
>                         {
>                                 error ( 0, 0, _("invalid step length"));
>                                 usage (EXIT_FAILURE);
>                         }
>
>                 if (!(isupper(first) || islower(first)))
>                         {
>                                 error ( 0, 0, _("invalid first character"));
>                                 usage (EXIT_FAILURE);
>                         }
>
>                 if (!(isupper(last) || islower(last)))
>                         {
>                                 error ( 0, 0, _("invalid last character"));
>                                 usage (EXIT_FAILURE);
>                         }
>
>                 if (isupper (first) != isupper (last))
>                         {
>                                 error ( 0, 0, _("first and last character must have same case"));
>                                 usage (EXIT_FAILURE);
>                         }
>
>                 if ((step > 0) == (last > first))
>                         {
>                                 for( ; (step>0)?(first <= last):(first>=last); first+=step )
>                                         printf( "%c\n", first );
>                         }
>         }
>   else
>         {
>                 last = scan_double_arg (argv[optind++]);
>
>                 if (optind < argc)
>                         {
>                                 first = last;
>                                 last = scan_double_arg (argv[optind++]);
>
>                                 if (optind < argc)
>                                         {
>                                                 step = last;
>                                                 step_is_set = 1;
>                                                 last = scan_double_arg (argv[optind++]);
>
>                                         }
>                         }
464a528,529
>         }
>