This function is a handy replacement for 'menu' for some specific cases where
you don't want a complex label structure - like, for example, asking simple yes-
no questions. It will return the number of menu option picked, starting with 1.
Like 'menu', it will also set the variable @menu to contain the option the user
picked.

if (select("Yes","No")==1) mes "You said yes, I know.";

And like 'menu', this command has a problem with empty strings - if some of the
option strings given to it are empty, you won't be able to tell which one the
user really picked. The number it returns will only make sense if all the empty
strings are last in the list of options.

prompt works almost the same as select, except that when a character clicks
the Cancel button, this function will return 255 instead.