[Freeciv-Dev] Re: [RFC PATCH] init_techs

[Arien Malec <arien_malec@xxxxxxxxx>]

--- Justin Moore <justin@xxxxxxxxxxx> wrote:
>    If the command they entered was invalid, tell them so.  The command
> struct could easily be modified to facilitate a change by associating a
> function pointer with it.  Thus:
> 
> typedef void (*command_func)(char *args);
> 
> struct command {
>   char *name;              /* name - will be matched by unique prefix   */
>   enum cmdlevel_id level;  /* access level required to use the command  */
>   char *synopsis;          /* one or few-line summary of usage */
>   char *short_help;        /* one line (about 70 chars) description */
>   char *extra_help;        /* extra help information; will be line-wrapped */
>   command_func *fptr;      /* Pointer to a callback function */
> };

To allow functions that take a list, the command should have a content model:

enum command_content {
   CMD_STR,
   CMD_INT,
   CMD_STR_LIST,
   CMD_INT_LIST
};

Or something. Otherwise the callback functions have to typecheck their
arguments. If the parsing code typechecks, the callback functions can be:

typedef void (*int_command_func) (int);
typedef void (*str_command_func) (char *);
typedef void (*int_list_command_func) (int, int *);
typedef void (*str_list_command_func) (int, char **);

(For the list callbacks, the first function is the size of the list).

Arien

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