README.Minimal

Instructions on using Minimal.db
------------ -- ----- ----------

The Minimal database is really quite minimal; there are no commands defined
other than the built-in ones (`PREFIX', `SUFFIX', and `.program') and only
enough verbs defined and/or programmed to make it possible to bootstrap.  It's
almost a certainty that you'd better off starting from the most recent release
of the LambdaCore database and possibly trimming things from that.  Some people
can't resist a challenge, though, so this document exists to orient them to the
meager contents of the Minimal database.

There are four objects in the Minimal database, arranged in the parent/child
hierarchy as follows:

	Root Class (#1)
	  System Object (#0)
	  The First Room (#2)
	  Wizard (#3)

The System Object has one defined verb, #0:do_login_command, which simply
returns #3.  This has the effect that all connections to the Minimal database
are automatically logged-in to Wizard, the only player.

The First Room has a verb named `eval' defined but not yet programmed.  It has
arguments `any any any' and permissions `rxd'.

The Wizard is initially located in the First Room and the other three objects
are initially located in #-1 (i.e., nowhere).

There are no other properties or verbs defined in the database.  There are no
forked or suspended tasks either.

The only way to get started in the Minimal database is either to change the
program for #0:do_login_command to perform some useful task (probably a more
tedious way to go, since you'd have to reconnect to get that verb to run), or
to provide a useful definition for `#2:eval' (probably the right course, since
you can invoke that more easily).

Of course, there are no restrictions on what you make this `eval' verb do, but
I recommend that you implement a simple, general MOO-code expression evaluator,
perhaps using code like this:

	.program here:eval
	notify(player, toliteral(eval("return " + argstr + ";")[2]));
	.

Or, perhaps something a tad fancier, to help you diagnose syntax errors more
easily:

	.program here:eval
	answer = eval("return " + argstr + ";");
	if (answer[1])
	  notify(player, tostr("=> ", toliteral(answer[2])));
	else
	  for line in (answer[2])
	    notify(player, line);
	  endfor
	endif
	.

Of course, much fancier `eval' verbs are possible, but you'll discover them for
yourself, I'm sure.

From such a basis, you can do anything by using the various built-in functions
directly, like add_verb(), add_property(), etc.  With sufficient amounts of
work, you can build up a set of easier-to-use command-line interfaces to these
facilities to make programming and building much easier.

If you should decide, after reading this, to build up an interesting database
starting from the Minimal one, and you succeed in doing so, please drop me a
line; I'd love to hear about it.

	Pavel Curtis
	aka Haakon, ArchWizard of LambdaMOO
	Pavel@PARC.Xerox.Com