Topic: @locks and locktypes
Author: Raevnos
Summary: Raevnos demonstrates the use of @lock and assorted locktypes.

Raevnos says, "Locks are used to control access to objects in various ways -
who can pick up an object, who can go through an exit, who can use commands on
an object, and so on."

Raevnos says, "I'm not going to cover the various types of locks, but rather
how to make them. See HELP LOCKTYPES for all the different locks and what they
do."

China nods.

Raevnos says, "Locks are set with @Lock/<type of lock> <object>=<lock>. If no
type-of-lock is given, the default 'Basic' lock is used. An empty lock clears
it."

Raevnos says, "The simplest kind of lock is one that's not there. If a lock
type is looked up on an object and not found, that lock is passed."

Raevnos says, "Otherwise, it's evaluated to see if the object being tested
passes or fails the set lock."

Raevnos says, "There's a bunch of different tests that can be used in locks,
as well as ways to combine them."

Raevnos says, "The simplest to use is just a dbref, *playername, or the name
of a nearby object. Either that object, or one carrying it, will pass the
lock."

Raevnos types --> @lock demo=#1234
Locked.

Raevnos says, "Putting a = before the dbref or name to match restricts it to
just that object, and not things holding it."

Raevnos types --> @lock demo==#1234
Locked.

China says, "aah."

Reavnos says, "A + restricts it to objects carrying that object."

Raevnos types --> @lock demo=+#1234
Locked.

Raevnos says, "Two tests can be combined with a |, which is a OR. If the test
on the left side of the | passes, the lock passes. If it fails, and the test
on the right side passes, the lock passes. Otherwise it fails."

Raevnos says, "So a lock of #1234 is equilivant to =#1235|+#1234"

Raevnos says, "You can also combine locks with &, which is AND. The tests on
both sides of the & must both pass for the lock to pass."

Raevnos says, "And a ! before the test will reverse it. !=#1234 will pass for
any object /but/ #1234, instead of just #1234."

Raevnos says, "A lock test starting with $ compares owners. $#1234 will pass
for any object that has the same owner as #1234. Since players own themselves,
this is an easy way to allow any of a given player's objects to pass a lock."

Raevnos says, "Or to fail to pass it. '@lock/page me=!$*twink' is a quick way
of stopping someone who's been harrassing or spamming you from being able to
do so."

Raevnos says, "You can also tell a lock to use the same lock type, but on a
different object, with @. For example, '@lock/use #4321=@#1234' will set
#4321's use-lock to #1234's use-lock. This is useful if you have a complex
lock you want a bunch of objects to share."

Raevnos says, "A test like 'NAME:PATTERN' will look up the attribute NAME on
the object that's trying to pass the lock, and pass if it's contents match
PATTERN. So, for example, to lock something to only players with a female sex,
'@lock foo=sex:F*'. The object the lock is on has to be able to get() the
attribute for this to work, so it's usually best to use it for attributes that
are normally visual."

Raevnos says, "The last lock type is the evaluation lock, the most powerful
type of test. It looks like 'NAME/VALUE'. The attribute NAME on the object the
lock is on is evaluated, and what it returns compared to VALUE. If they match,
it passes, otherwise it fails."

Raevnos finishes his rehash of the help files. Any questions?

China says, "yes sir. If I may."

Raevnos says, "Ask away."

China says, "on your one of the !=#1234 ...is the ! actually on the side of
the obj's db# of the = sign?"

Raevnos says, "Before the =."

Raevnos says, "=!#1234 doesn't work."

China says, "so it would be set up like @lock obj!=#1234 and all but 1234
could use it."

Raevnos says, "Ah. No. The first = is for the @lock command, to split the
object to set the lock on apart from the lock itself."

China says, "like @lock obj !=#1234?"

Raevnos says, "'@lock foo==#1234' is split into 'foo' and '=#1234'."

Raevnos says, "So it'd be @lock foo=!=#1234"

China says, "OH! Ok."

China says, "another question and jprobably jsut me being confused. On the
@lock/use #4321=@#1234 you said it would allow "all" of #1234's objects to use
it besides owner's?"

China says, "or would you also have to have the $ in there too?"

Raevnos says, "@ is used to point to a lock on another object. $ checks for a
common owner."

China thinks on this.

Raevnos says, "In that example, anything that passes #1234's use-lock would
also pass #4321's use-lock, because they basically have the same lock."

China says, "I think I see what your saying."

China says, "lastly ...would you be kind enough to give an example of a value
lock?"

China says, "I don't know what a value is."

China says, "but you don't have to explain value. That's a different subject.
I'd just like to see such a lock."

Raevnos says, "You mean an evaluation lock? The name/value one?"

China says, "yes, Sir. That one."

Lock Demo/ISADMIN - Set.
Locked.
Lock Demo(#3903Vn)
Type: Thing Flags: VISUAL NO_COMMAND
Owner: Raevnos Zone: Raevnos' ZMO(#1398) Ducats: 10
Parent: *NOTHING*
Basic Lock: isadmin/1
Powers:
Warnings checked: none
Created: Tue Sep 26 20:16:40 2000
Last Modification: Tue Sep 26 20:48:19 2000
ISADMIN [#1622]: orflags(%#, Wr)
Home: Code Classroom(#1061RnJ)
Location: Code Classroom(#1061RnJ)

Raevnos says, "examine lock demo"

Raevnos says, "That checks for a wizard or royal flag on the object trying to
pass the lock."

China says, "aah. Thank you."

China makes a note that flags are values.

Raevnos says, "Checking for a set flag is such a common thing in evaluation
locks that it'll probably be made it's own test sometime in the future, to
save on having to look up and evaluate an attribute every time."

China says, "you mean like a @lock/<flag name> obj= #1234?"

China says, "sorry. I'm always thinking and asking questions beyond the
subject. Didn't mean to ask."

Raevnos says, "No, something like '@lock/use foo=flag:wizard|flag:royalty',
though that uses the attribute-lock syntax, so it'll probably look different.
I just haven't decided on a form."

China says, "I'm not very good at figuring out the helps syntax examples. So I
really do appreciate thast you gave examples of the locks."

China looks quickly over her notes again to see if she missed any questions.

China says, "oh... what did you mean by the simplest lock is the one not on
the object. How if it's not there and is passed, is it a lock?"

Raevnos says, "It's just automatically passed if it's not set. A lock that
doesn't actually lock anything."

China says, "aaah, ...ok, and may I ask a quesion on a type of lock you didn't
mention? The @chan/join <channel> =<key> types? Might you show an example of
that...as I don't know what the brackets mean, or what they want for a key?"

Raevnos says, "@clock/join, not @chan/join. <key> is what I called <lock>.
Something like '=#1234|=#1235|=#1236' to restrict a channel to just a few
people."

China says, "yes, sir. I typed it wrong your correct. So the <key> is a list
of allowed players and not an object the one setting who can join, is
carring."

Raevnos says, "It can be (almost) anything that works with a normal @lock.
Evaluation locks don't work because channels don't have attributes. An
indirect lock to an object that has a lock that does the right thing is needed
then. @clock/join channel=@#1234"

Raevnos says, "The lock name that's checked on #1234 is mentioned in the help
somewhere."

Raevnos says, "HELP @CLOCK2"

China says, "I do read the helps several times over ...but then a lot of the
syntaxs, if there's no example, I just flat out don't know what to type some
times. That was one I jsut didn't know what it wanted."

China nods understanding your explination. Now is seeing she can't presently
find any more questions.

China says, "I'm sure I'll have more as I get into doing more with them. :)"

Raevnos grins.

China folds her notebook, not having any more questions that she can find.