notify_fail |
Discworld driver help |
notify_fail |
Name
int notify_fail( string | function str );
Description
Store `str' as the error message to be returned instead of the default message `What?'. The message will be displayed if a 0 is returned from all actions setup via add_action(). This is the preferred way to display error messages since it allows other objects a chance to respond to the same verb (command). Do not use write() to display the error message since this will require you to return a 1 (unless you want to see the result of the write() in addition to the 'What?' message). However, if you do return a 1, then no other objects will get a chance to respond to the user command.
Note: Getting this right in the presence of multiple failures is tricky, to say the least. One can use a function pointer instead, and have the routine resolve the collisions.
If a function is passed instead of a string, the function is called instead of printing a message. If the function returns a string, that string is used as the failure message. Also, this_player() is set correctly, so write() can be used.
If notify_fail() is called more than once, only the last call will have an effect.
The idea behind this function is to allow better error messages than `What?'.
As a side note, notify_fail() always returns zero, so return notify_fail(...) works as expected.
