Programmer's Guide to MOZ (Moo in OZ).

Node: Top, Next: , Up: (dir)

This is the Programmer's Guide for MOZ (Moo in OZ). MOO is Mud Object Oriented. MUD is Multi-User Dungeon or Dimension. In general, a MUD is a multi-user text-based virtual environment. For information on MUDs in general, see http://www.godlike.com/muds/ or your local search engine. For information on MOOs, see http://www.moo.mud.org/moo-faq/.

Oz is a multi-paradigmatic language that happens to not suck. See http://www.mozart-oz.org/.

Node: General Issues, Next: , Previous: Top, Up: Top

General Issues

Node: Introduction, Next: , Up: General Issues

Introduction

***UNFINISHED***

Node: Localized Strings, Next: , Previous: Introduction, Up: General Issues

Localized Strings

To deal with MOZ's requirement to be able to output to users in multiple languages, a MOZ programmer should never use Oz strings for output at all. Instead a structure called a Localized String is used. This is a record, with a feature for each language (using whatever short code is defined in the Server object, such as en for English). Each feature holds a string that is the string that should be output for a user that uses that language. An example: 

     string(
         en: "A sample string.\n"
         lb: ".i le mupli seltcidu\n"
     )

However, for output of strings from program code (as opposed to output of strings set by players directly, such as those stored in names and descriptions), you shouldn't enter these strings directly. Instead, you should first add the strings to the LanguageStrings object using the ***UNFINISHED*** command. The tell method on the Player object will treat any atom by itself as a key into the database on LanguageStrings, making it easy to use these strings in your code.

The reason to do this is it makes it much easier for others to translate everything in the MOZ to a new language if everything is collected on one object and easily retrievable.

Node: Timeouts, Previous: Localized Strings, Up: General Issues

Timeouts

When you call another object in Oz (or do anything else, for that matter), the program happily waits until processing is completed, and will happily wait indefinately. This is a bit of a problem in a language where many bugs cause hangs.

While there's not much MOZ can do to stop you from causing a hang in your own code, there are timeouts on calls to other objects, so that another object being hung doesn't permanently hose your own code.

The default timeout is 500 microseconds (i.e. half a second). To alter this timeout, add the feature activeObjectWaitTime to the method call with the feature holding a positive integer representing the timeout you want, or nil to wait forever.

Note that the method making the call may also be under a timeout, so waiting 3000ms when the callee will timeout in 500ms is rather pointless.

Verb calss have the rather grotesque timeout of 6 minutes. start methods never timeout.

Node: Class Creation, Next: , Previous: General Issues, Up: Top

Class Creation

**UNFINISHED** Here go some notes about what classes are and why you would want to create one.

Node: Class Creation Introduction, Next: , Up: Class Creation

Class Creation Introduction

**UNFINISHED** Stuff about why you'd want to create classes (especially since this is the fundamental thing that makes one a MOZ programmer), stuff about class items and how to use them to control classes.

Node: Creating A Class File, Next: , Previous: Class Creation Introduction, Up: Class Creation

Creating A Class File

create class named className Variable
Use this command to create a class you can edit. Actually, it technically only creates an object of class ClassControl, which you then use to write and compile the class.

write class className Variable
Takes text until you enter "EOF" on a line by itself, and puts that text in the class file. You must have run create class for this to work.

compile class className Variable
Compiles a class written using write class. Note that if your class has certain types of bugs, this will hang. You will be able to continue your activity in the MOZ, though, and try again if you like.

Node: Required Attributes And Features, Next: , Previous: Creating A Class File, Up: Class Creation

Required Attributes And Features

**UNFINISHED**

Test.

Attributes

name
A localized string containing the object's name in the MOZ.
storageRef
The storageRef attribute just holds an object reference record for the MOZ's central Storage object. _Every_ object in the MOZ needs to talk to Storage at some point.
languageStringsObjectRef
Holds the global set of localized strings, which all system object should use.
hasProperName
A boolean declaring if the object's name is a proper name (like Alice or Bob) or a generic name (like couch or door or puppy).
verbs
A place to store the list of input verbs that this class recognizes. Note that there are special methods to deal with this structure; it should not be touched directly.
publicMethods
This is a list of methods we let everybody see. In particular, this list is used to give basic capabilities to an object's location, and vice versa.

The list is updated using addPublicMethod.

serverRef
The serverRef attribute just holds an object reference record for the MOZ's central Server object.

Features

ozName
The ozName feature; holds an Oz name value unique to the current object.
exports
The exports feature holds a list of 2-tuples detailing the attributes to be handled by toRecord and fromRecord. In other words, it lists all attributes that need to be saved to disk to preserve the state of a member of this class, so it is very important to fill exports properly.

The 2-tuples are the name of the attribute and its type. Most type atoms are ignored, but some must be specially handled (i.e. object references, which must be mediated by the Storage object).

A minimal example: 

              exports: [
                  storageRef#objectRef
                  serverRef#objectRef
                  languageStringsObjectRef#objectRef hasProperName#bool
                  name#string
              ]

A more complicated example, with multiple inheritance: 

          exports: {Append
              {Record.toListInd
                  {Adjoin
                      {List.toRecord exports Location.exports}
                      {List.toRecord exports Mobile.exports}
                  }
              }
              % Our local exports
              [ language#atom outputPort#notPersistent ]
          }

featExports
featExports is just like exports, except for features instead of attributes.

A minimal example: 

              featExports: [ ozName#name capabilityDict#dict ]

methodList
The methodList feature just holds a list of the names of the methods that the wrapper should make capabilities for, i.e. the externally available methods. Note that upgrade should not be here, because it's handled specially.

A minimal example: 

              methodList: [
                  init start stop ozName className toRecord fromRecord revoke
                  hasProperName getName setName deLocalize getVerbs addVerb
              ]

A more complicated example, with multiple inheritance: 

              methodList: {Append
                  {Merge
                      {Sort Location.methodList Value.'>'}
                      {Sort Mobile.methodList Value.'>'}
                      Value.'>'
                  }
                  % Our local methods.
                  [
                      tell setLanguage getLanguage sayVerb setStorage
                      reloadVerb languagesVerb languageVerb helpVerb
                  ]
              }

className
The class name, stored as an atom: 
              className: 'MozBase'

capabilityDict
The capability dictionary for this object.
wrapper
The active object wrapper procedure for this object.

Node: Common Methods, Previous: Required Attributes And Features, Up: Class Creation

Common Methods


start
The start method is run everytime a new object is created, which includes when it is first loaded into the MOZ or upgraded, as well as at other times in some cases.

The start method is normally either passed the boolean isForUpgrade feature if the start is being run during an upgrade (which can require special processing) or nothing at all.

stop
The stop method works like the start method in all respects except that it is run before the object is shut down or upgraded.

Node: Control Objects, Next: , Previous: Class Creation, Up: Top

Control Objects

Every object that is created causes the creation of a control object so that the player can do arbitrary things to the object they just got. This section describes some details about control objects that a programmer needs to know.

Control objects are of class Control, which is a child of class Mobile.

Node: Control Verbs, Up: Control Objects

Control Verbs

Control objects don't use the normal verbs of their class, because they need to provide functionality base on the class they are controlling.

However, we don't want every verb available on the base object to be available on the control object (you can't go through a control object for an exit, for example) and more importantly, the verbs availble on the control object must not be available on the controlled object (we don't want to let just anybody link an exit, for example).

So, here's how you extend the control functionality of control objects made for a class you've created. It's actually fairly simple.

First, create the verbs as normal, but instead of using addVerb, use addControlVerb.

Second, and this is very important, make sure that the verb methods for control verbs are not public.

Thirdly, instead of using self when referring to the object being controlled, use @controlled.

Node: Verbs, Next: , Previous: Control Objects, Up: Top

Verbs

Methods that do the processing for a verb call have special default arguments that are sent to them, as well as needing to return a specialized result value.

Node: Verb Methods, Next: , Up: Verbs

Verb Methods

Verb Methods Are Always Public

Except for the special case noted in See Control Verbs, methods used for a verb must always be publicly accessible, or they won't be usable. This just means adding a call like this to the init method on the class: 

     {self addPublicMethod( method: myVerb ) }

Verb Method Default Arguments

caller
The objectRef for the calling object.
player
The objectRef for the player object.
language
The language of the verb itself, for when the player is able to run verbs in multiple languages (i.e. help has language en, sidju has language lb).
result
The result of the verb, a record that indicatats success or failure of the method, among other things. It is described thoroughly in the next section. If the result is not set, success is assumed.
force
If force is set to true, no checking should be done to see if the current object is the one the verb call was intended for: it is assume that this object is, in fact, the correct choice. Such checking would be things like name and alias matched, for example.

Verb Method Result Records

The result argument gets filled with a with a record similar to the pseudo-code one below: 

     result(
         status: success|failure|other  -- default success
         certainty: float from 0.0 through 1.0 -- default 1.0
         comments: <localized string> -- default nil, only relevant to failures
     )

There are a couple of problems that this structure is intended to address.

The first is that we want the option of delivering a specialized failure message from whichever object and method knows best what the problem was if things didn't work. The difficulty there is that many failure will be from objects that really are *not* the one the verb call was intended for, so we don't want to return their errors to the user.

The second problem is that on object might honestly not be sure if a verb call, that would in fact be successful, is meant for itself. For example, if an alias is used, or the name matches but only in a case-insensitive fashion, those matches should introduce some doubt as to whether the object in question is really the one the verb call was intended for.

The solution to these is the certainty field. The certainty field is a number from zero (0) to one (1), inclusive, which indicates how certain the verb method is that it was the intended target for the original verb call. In the case of target uncertainty, the status should be 'other'.

The certainty field is ignored if the status is success.

If no status field was set to success out of a group of verb method checks, the result records are sorted by certainty. The highest non-zero value whose status is *not* failure is called again with the force argument set to true. This selects, out of the methods that weren't sure they was being talked to, the method that was most sure it was the intended target. Verb methods should skip all certainty checks when force is set to true.

If there are only failures, the failure with the highest certainty has its comments field de-localized and sent to the player to help them figure out what happened.

Note that non-verb methods often also have result arguments. If so, they will often not return a certainty feature as part of their result record, because that sort of thing is the verb method's job to determine.

Node: Verb Record Structure, Previous: Verb Methods, Up: Verbs

Verb Record Structure

Please note that this first section is largely not something you need to use: the addVerb method allows you to avoid most of the technical details. The section on Parse Records, on the other hand, is quite important.

Verb records are used to associate particular types of user input with methods on objects. This means that when you type "list languages", a verb record somewhere (on your Player object, in fact) is used to compare against that to find out what method to call (in this case, the 'languagesVerb' method).

Verb records are stored in the verbs attribute. The verbs record has features for each language that the object has verbs on, like so: 

     verb: allVerbs(
         en: <verb records>
         lb: <verb records>
     )

The label of the record, in this case allVerbs, is irrelevant, as are the labels of all records in this section, unless specificially mentioned otherwise.

The verb records themselves contain one feature for each verb word (that is, the first word of input) that the object wants to accept, like so: 

     en: verbs(
         help: <verb record>
         languages: <verb record>
     )

Each actual verb record contains the language the verb was called in1, and the parsing structure: 

     help: help(
         language: en
         parses: [
     	helpVerbParseName(
     	    method: helpVerb
     	    endOfInput: nil
     	)
         ]
     )

The parses feature and its list are both complicated and unusual, and are discussed in the next section.

Parse Records

The parses list is something that is very unusual for a MUD: it allows each verb to define how its arguments are parsed, and in fact requires that each verb do so.

Normally, a MUD understand some basic linguistic structures of one language, and attempts to shoe-horn whatever the player says into what it understands. For example, it might understand the English concepts of subject, preposition, and object, and will attempt to understand all input in those terms.

MOZ, on the other hand, allows each verb in each language to define how it wishes its input to be broken up. It attempts to do this in a way that requires as little programming knowledge as possible, but it's still not exactly simple.

The parses feature is, in fact, a list of records. This is used so that one verb word can access different methods, depending on how the rest of the line is parsed.

Important: the label of the individual parse records, such as helpVerbParseName above, must be unique within the verb in question on whatever object the parse record is being added, as addVerb uses that label to decide what to override when you update the verb.

The record structure for the records inside the parses list is as follows: the method feature contains the name of the method, whatever feature is left after that feature is removed (there should be only one) is used as the first parsing directive.

In this example: 

     help: verb(
         language: en
         parses: [
     	playerHelpVerb(
     	    method: helpVerb
     	    endOfInput: nil
     	)
         ]
     )
the first, and only, parsing directive is endOfInput, which sees if the end of the user input has been reached2. This means that nothing, other than whitespace, can follow the verb word "help" for this parsing structure to match.

On the other hand, we have: 

     list: verb(
         language: en
         parses: [
             playerListLanguagesVerb(
                 method: languagesVerb
                 matchWord: matchWord(
                     word: "languages"
                     rest: rest(
                         endOfInput: nil
                     )
                 )
             )
             playerListHelpVerb(
                 method: helpVerb
                 matchWord: matchWord(
                     word: "help"
                     rest: rest(
                         endOfInput: nil
                     )
                 )
             )
         ]
     )
which matches either the word languages, then end of input, or the word help followed by end of input. In the two cases, different verbs are called.

In some cases, there will be parse records inside a parse directive; in this case, matchWord has a feature, rest, which is used to match everything after whatever word matchWord is being used to match. These parse sub-records work just like the general parse records described here, except they cannot be lists, the must be single records, and they should not include a method feature.

Parsing Directives

Directive Name Arguments Effect
endOfInput nil Matches end of character input.
string any 1 atom Bind the longest string (i.e. series of space-seperated words) it can find to the atom passed to it, which is passed to the verb's method. A word is a list of anything that Char.isGraph returns true for. Because of this, string pretty much always matches the entire rest of the line. So, for example, "string: inputString" will pass the argument inputString to the verb's method containing the rest of the line.
stringUntil until string rest Fills string with words until it reaches a word that matches the word (or list of words) stored in until.
matchWord word rest The word argument should contain a string with the word that needs to be matched in the input. rest contains a full parse tree.
getWord word rest The word is filled with the next word in the input. rest contains a full parse tree.
plus first second This is the choice operator. Evaluates first as a full parse tree. If the parsing of first succeeds, returns that. Otherwise, tries to parse with second, returning that if succesful. Otherwise fails.
multiMatchWord words wordFound rest Attempts to match anything from the list of strings in words. Whichever word is actually matched is given to the method in the atom named by wordFound. rest is the parse tree for everything after that word.
article wordFound rest Same as multiMatchWord with words set to the contents of the articles attribute on the Parser object.
mayHaveArticle wordFound rest Same as article, but accepts strings that don't start with an article as well.
bracket left right rest Matches anything entirely inside the brackets defined by left and right. Works if both left and right are words or if both are single characters, but not for a mix of the two. Note that it does not deal with nesting in any real way, and will only succeed if the first word or character in that part of the parse matches left and the last matches right, regardless of what's in the middle.

Node: Core Classes, Next: , Previous: Verbs, Up: Top

Core Classes

Node: Core Methods, Up: Core Classes

Core Methods

This is a list of methods on the core classes, for use in your programs. If it's not listed here, that's probably because the documentation is out of date, not for security reasons or anything; MOZ is a capablitiy-based system, if you want to shoot yourself in the foot, that's fine. Please inform the author of all missing entries.

Note that this is a very brief treatment of the various methods; details should be gleaned from the source code.

Note further that verb methods are not listed here, because they cannot be called directly, and they can be deduced from the list of commands anyways.

Node: MozBase Methods, Next: , Up: Core Methods

MozBase Methods

init ozName storageRef serverRef languageStringsObjectRef Method on MozBase
Initializes the attributes storageRef, serverRef and languageStringsObjectRef and the feature ozName to the values passed.

start Method on MozBase
None Does nothing; here to be over-ridden in other classes.

stop Method on MozBase
None Does nothing; here to be over-ridden in other classes.

ozName ozName Method on MozBase
Returns the Oz Name associated with the current object in the passed variable. Would normally be named getOzName, but this method is used very frequently, and the value can't be changed so there would be no corresponding setOzName anyways.

className className Method on MozBase
Returns the Oz Name associated with the current object in the passed variable. Would normally be named getClassName, but this method is used very frequently, and the value shouldn't be changed so there would be no corresponding setClassName anyways.

toRecord record Method on MozBase
toRecord is a very important method that runs through the elements of the exports feature and constructs a record using the information therein. This record can be pickled, saved to disk, and later loaded in with fromRecord.

fromRecord record convert objectRef Method on MozBase
fromRecord is the inverse operation to toRecord. It takes the output of toRecord and sets attributes appropriately. Note that this is a pure procedure: it is only called for its side effects. convert is the procedure to convert stored attributes of type objectRef into something useful, gotten from the Storage object. objectRef is used to return an object reference to the newly initialized object, with all capabilities.

revoke method capability newCapability Method on MozBase
Revokes the current capability on the given method, assuming that the argument capability matches it. The new capability on that method is returned in newCapability.

hasProperName hasProperName Method on MozBase
Returns a boolean declaring if the object's name is a proper name (like Alice or Bob) or a generic name (like couch or door or puppy).

setHasProperName hasProperName Method on MozBase
Sets the hasProperName to true or false.

addVerb language verb parse Method on MozBase
Adds a verb to the objects verbs record, dealing with things like over-writing the same verb parse, dealing with multiple parses of the same verb, and the fact that the whole verb record system is very baroque.
language
The language the verb applies in.
verb
The verb word itself ("help", "look", whatever).
parse
The parse record to add. Note that this record will over-ride any other parse record for the same verb with the same label, so it's important that it be reasonably unique.

getName name Method on MozBase
Standard variable get.

getArticledName name Method on MozBase
Returns the object's name with the appropriate article in front of it.

getArticledStarterName name Method on MozBase
Like getArticledName, but adjusts for the article being the first word of a sentence if a language requires that.

setName name Method on MozBase
Standard variable set.

getVerbs verbs Method on MozBase
Standard variable get.

deLocalize inputString outputString language Method on MozBase

Returns a bare string from a localized string, based on a language argument.

Arguments:

inputString
The string to be de-localized, in string( lang: <string> ) format as usual.
outputString
A normal Oz string.
language
Optional, the language to de-localize into.

selfMatch string certainty language Method on MozBase
The object returns a certainty, as a value from 0 to 1, that it is the object being referred to by the string in question. The string should be localized.

Possible Certainty Values:

1.0
A perfect string match, including case.
0.9
Matches only after converting both strings to lower case (i.e. a caseless match).

addPublicMethod method Method on MozBase
Adds the given atom to the list of public methods for this object (i.e. methods for which capabilities are given out freely).

enhanceStorage storageRef Method on MozBase
Adds the capabilities on the given storageRef to the object's current capability set for the Storage object.

selfReference selfRef Method on MozBase
Returns a complete reference for the current object, including all capabilities. Very insecure!

publicSelfReference selfRef Method on MozBase
Returns a complete reference for the current object, with capabilities for only the methods in publicMethods.

printedList stringList string Method on MozBase
Takes the list of strings in stringList and concatenates them together as might be expected in a natural language string (i.e. in English, using commas and "and").

printedObjectList objectList string Method on MozBase
Like printedList, but the list is a list of object references, from which names are extracted.

Node: Storage Methods, Next: , Previous: MozBase Methods, Up: Core Methods

Storage Methods

start args modules serverObjFileNum realStart newMoz Method on Storage
Extracts command line arguments from args, sets up links to external Oz modules, and if serverObjFileNum is passed, set the internal file number where the Server object is known to reside to that number. This only happens when the MOZ is being re-initialized.

newMoz is used to tell the method that this is the initialization of a completely new moz.

sync None Method on Storage
Syncs all MOZ objects to disk.

stop None Method on Storage
Saves all MOZ objects to disk.

info None Method on Storage
Outputs debugging information; currently all commented out.

init ozName fileNumToOzName storageRef languageStringsObjectRef Method on Storage
Initializes a new Storage object, mostly using MozBase,init. fileNumToOzName is a dictionary that normally only contains a mapping from the number 1 to the new Storage object's Oz name. Initializes some other dictionaries.

loadClasses None Method on Storage
Compiles and loads all the MOZ's .class files.

loadObject fileNum objectRef init Method on Storage
This method loads an object from the disk by its number (using the fileNumToOzName dictionary). It returns the object record in objectRef.

saveObject objectWrapper ozName Method on Storage
This method saves the object information to disk. Note that objectWrapper is just the Active Object wrapper, not the standard object reference object.

createObject className objectRef ozName init Method on Storage
Creates an object, returning a standard object reference in objectRef.

getClass className class Method on Storage
Returns the class code for the given className

upgradeObject objectRef className newObjectRef Method on Storage
Upgrades the given object to the given class, returning newObjectRef. Note that this could be the same class name as before, but the class itself has been re-loaded in the mean time. In fact, that should be the most common type of upgrade.

getObjectFileNum objectRef fileNum Method on Storage
Take an object reference record and returns the file number associated with that object reference. Not for general use!

getServerObjFileNum serverObjFileNum Method on Storage
Returns the file number for the Server object. Not for general use!

setServerObjFileNum serverObjFileNum Method on Storage
Sets the file number for the Server object. Not for general use!

getObjectFromFileNum fileNum objectRef Method on Storage
Retrieves an object given the file number it is stored in. Not for general use!

objectRefFromRecord convert Method on Storage
This is the procedure that fromRecord needs to instantiate attrs of type 'object'. Full details are in the source.

This is so far from being for general use that it's not even funny.

logLevel level Method on Storage
Set the current logging level to level. Logging levels are, in order from most to least verbose, debug, info, warn, error, and critical.

The default is warn. For whatever level is selected, that level of log message and above (above meaning "less verbose" or "more severe") are printed.

getConnectionModule module Method on Storage
Returns a copy of the Connection module. That's the Oz Connection module, NOT the MOZ Connection class. Used by the Gate and Terminus classes.

getPickleResult url pickleResult Method on Storage
Treats url as the URL to a file containing an Oz pickle, and returns the result of attempting to un-pickle that file. Used by the Gate class.

writePickleToFile file value Method on Storage
Writes the given value, as an Oz pickle, to the file given. The file is stripped of "/" and "\" characters, and placed under the "pickle" directory under the server's root directory.

getCapabilitiesFromOzName ozName capabilities Method on Storage
Returns a full set of capabilities for the object associated with the ozName given.

getObjectFromOzName ozName objectRef Method on Storage
Returns an object refrence, including a full set of capabilities, for the object associated with the ozName given.

getObjectFromFileNum fileNum objectRef Method on Storage
Returns an object refrence, including a full set of capabilities, for the object associated with the file number given. Please don't use this.

upgradeObject objectRef className Method on Storage
Forces an upgrade of the object in question.

upgradeAll done Method on Storage
Upgrades *all* objects in the MOZ. Well, OK, all the ones Storage knows about (which is everything but special user-created stuff, for which you're on your own).

createClass className controlRef result Method on Storage
Creates a ClassControl object for the given className, after checking that no such class already exists, and returns a reference to the new object in controlRef.

writeClassFile className string result Method on Storage
Writes the class file associated with the given className using the string given as the entire text of the class file.

loadClass className Method on Storage
Recompiles the class named className. Not that the actual compilation is threaded off.

Node: Server Methods, Next: , Previous: Storage Methods, Up: Core Methods

Server Methods

init ozName storageRef languageStringsObjectRef storageObjectRef startRoom Method on Server
As per usual, except for storageObjectRef, which passes extra, better capabilities to the Server object, and startRoom, which passes and object reference to the player starting room.

start args modules hold realStart Method on Server
As with Storage, except hold, which returns a variable that remains unbound until the server is shut down.

realStart is used to say that this is the real start call, rather then the normal one that happens when the object is created.

stop Method on Server
Stops the server; also binds hold from the start method.

handleLogin acceptObject playerRef outputPort acceptProc Method on Server
Deals with a user's attempt to log in, including creating new player objects if necessary. More details in the source.

upgradeStorage newClass convert Method on Server
Storage calls this to get the server to upgrade it during an upgradeAll call. No user servicable parts inside.

changePassword player oldPassword newPassword Method on Server
If the stored password for the login name player matches oldPassword, changes it to newPassword.

Node: Connection Methods, Next: , Previous: Server Methods, Up: Core Methods

Connection Methods

start socket storageRef modules parser outputStream Method on Connection
Handles the connection, reading from the TCP/IP port and passing to the parser, and then back.

Node: LanguageStrings Methods, Next: , Previous: Connection Methods, Up: Core Methods

LanguageStrings Methods

init ozName storageRef Method on LanguageStrings
Nothing unusual here.

getLanguageString key string Method on LanguageStrings
Simple dictionary lookup on the languageStrings dictionary. If the key passed as an argument does not exist, a blank, globally localized string is returned. )"

setLanguageString key string Method on LanguageStrings
Dictionary write on the languageStrings dictionary. Any languages not covered by the string argument are left as they were.

resetLanguageStrings Method on LanguageStrings
Reloads all of the default language strings. Note that if new languages have been added, they will not be overwritten; only the languages that ship with the server by default will be, and only in the original strings; no newly added strings will be affected.

Node: Parser Methods, Next: , Previous: LanguageStrings Methods, Up: Core Methods

Parser Methods

start storageRef modules outputPort serverStop player languageStringsObjectRef Method on Parser
Starts a new parser objcet. outputPort is the Socket object that is used for sending output to the player. player is an object reference to the player object.

parseOutVerb string result Method on Parser
Just extracts the first word from the input string, which is then treated as the verb word.

parse input Method on Parser
First tests to see if the first character, by itself, is a verb, using matchVerbs, then tries the whole first word, again using matchVerbs. If that fails, complains to the character.

runVerb verb rest result Method on Parser
Attempts to match the input verb against any verb it can get its hands on, starting with the player object, then the player's contents, then the player's room, then everybody in the room.

This method does not implement the verb record parsing strategy; it calls verbParseRest for that.

verb contains the verb word, rest contains the rest of the input, and matched is set to true if a match was found.

verbParseRest verbParse rest verbMethod language result Method on Parser
Implements parsing of verb records. Takes the parse segment of a verb record, and returns a record named after the verb word with the various arg1:, arg2: ... elements in it, filled according to the parse record.
verbParse
The parse record for the verb.
language
The language of the verb match we're working against.
result
The results of the parse, as a record named after the verb word with features named according to the parse record.

eval input Method on Parser
Evaluates the input as a piece of Oz code. 3

Node: Described Methods, Next: , Previous: Parser Methods, Up: Core Methods

Described Methods

init ozName storageRef name description Method on Described
Adds name and description attributes to the standard init.

getDescription description Method on Described
Standard variable get.

setDescription description Method on Described
Standard variable set.

deLocalize inputString outputString language Method on Described
Returns a bare string from a localized string, based on a language argument, using the MozBase version of the same methed but passing a value for the Server class. The Server information allows using the Server's default language value as a fallback.

Node: Located Methods, Next: , Previous: Described Methods, Up: Core Methods

Located Methods

init location Method on Located
Adds location to Described's list.

getLocation location Method on Located
Standard variable get.

Node: Mobile Methods, Next: , Previous: Located Methods, Up: Core Methods

Mobile Methods

setLocation location Method on Mobile
Standard variable set.

Node: Location Methods, Next: , Previous: Mobile Methods, Up: Core Methods

Location Methods

init contents Method on Location
Adds contents information to Described's list.

addToContents objectRef Method on Location
Adds the given object to the current contents list.

getContents contents Method on Location
Standard variable get.

getContentsString string Method on Location
Returns a string that contains a list of the names of all the objects in the object's contents list.

removeFromContents objectRef Method on Location
Removes the given object from the current contents list.

wantToGet newLocation origRecord newRecord Method on Location
This is called by other objects who desire to get one of the objects from our contents list. See get on Location. origRecord is a minimal object reference to the object that newLocation wants.

wantToGive oldLocation objectRef result Method on Location
This is called by other objects who desire to give us one of the objects from their contents list. See give on Location. result is set to true if we accept the object, false otherwise.

searchByObjectName name except objectRef result language Method on Location
Returns the object in our contents best matching the given name, else returns a standard result in result. except is used to exclude the calling object from the searching, as this will cause a hang.

announce string except Method on Location
This is called by other objects who desire to have a string presented to the tell methods of all objects in this location (at least, those _with_ tell methods).

The except argument takes an object reference and causes the string to not be presented to that object. This is very important, because if you call announce and the object making the announce call has a tell method, the announce will hand trying to re-enter that object. So, always put the object calling announce in the except argument!

get fromLocation objectRef Method on Location
Gets an object from another object, which must be a descendant of location.

First we call getFrom on the from location, then put the object that that call returns into our contents list.

Note that objectRef is limited reference to the object we want to get.

See wantToGet on Location.

give toLocation objectRef Method on Location
Gives an object to another object, which must be a descendant of location.

First we call wantToGive on the from location, then remove the object that we give to that call from our contents list if the call returns true. See wantToGive on Location.

Node: Container Methods, Next: , Previous: Location Methods, Up: Core Methods

Container Methods

init Method on Container
Merges the inits of Location and Thing; Location's init is run first.

Node: Player Methods, Next: , Previous: Container Methods, Up: Core Methods

Player Methods

init Method on Player
Runs the init methods for Location and Mobile (in that order). Sets language and outputPort to nil.

start modules outputPort realStart Method on Player
Sets the outputPort object variable.

realStart is used to say that this is the real start call, rather then the normal one that happens when the object is created.

stop Method on Player
Nothing special here, except during upgrades.

setStorage storage Method on Player
Just used to set the storage attribute with a new capability set. Used for wizardry and dewizardry and the like.

tell string language Method on Player
Sends a string to the user. The string can either be a single string or a list of strings. Any individual string can be either a localized MOZ string or a single atom. If it is an atom, that atom is looked up on the LanguageStrings object and the result is output.

setLanguage language Method on Player
Standard variable set.

getLanguage language Method on Player
Standard variable get.

setStorage storageRef Method on Player
Standard variable set, for storageRef.

grabInputUntil untilString inputString result Method on Player
Takes all input entered by the player until the player types the string passed in untilString. The input is returned in inputString. result is as per usual.

This method can only be called once every thirty seconds, to prevent malicious code from not letting the player interact with the rest of the MOZ. Further attempts to call this method will return a failure result instantly.

Node: Exit Methods, Next: , Previous: Player Methods, Up: Core Methods

Exit Methods

setDestination destination Method on Exit
Sets the destination for this exit to the object given.

setName name Method on Exit
Sets the exit's name. Also creates verbs corresponding to the new name, so the player can use the exit.

Node: Gate Methods, Next: , Previous: Exit Methods, Up: Core Methods

Gate Methods

setDestination destination Method on Gate
Sets the destination for this exit to the object referenced by the pickle stored at given url.

Node: Terminus Methods, Next: , Previous: Gate Methods, Up: Core Methods

Terminus Methods

getTicket ticket Method on Terminus
Uses the Connection module to return a ticket to itself.

writeTicket file Method on Terminus
Uses the writePickleToFile method on Storage to write a ticket for a reference to itself to the file given (which will be physically stored in the "pickle" directory under the server root directory).

Node: Control Methods, Next: , Previous: Terminus Methods, Up: Core Methods

Control Methods

getName name Method on Control
Generates a name based on the name of the underlying controlled object. For example, if the controlled object is named "Dead Parrot", this method will return "Control Rod For a Dead Parrot". Also updates the Control object's name attribute.

selfMatch Method on Control
Makes sure that its name is set properly, based on the current name of the controlled object, then runs the normal selfMatch method.

otherwise Method on Control
The otherwise method is priviledged in Oz: it is called for any method call that doesn't match anything else. It is used here to handle the extensibility of Control verbs and methods based on the underlying controlled object's class.

getMethodList methodList Method on Control
Returns the combined methods of the Control object and the controlled object.

getVerbs verbs Method on Control
Returns getControlVerbs on the underlying object.

start Method on Control
Generates a perfect object reference on the controlled object (i.e. one that can never lose capabilities) using a special capability set from Storage, and sets its name.

publicSelfReference Method on Control
Calls selfReference: with Control objects, possession is ten tenths of the law.

Node: ClassControl Methods, Previous: Control Methods, Up: Core Methods

ClassControl Methods

getName name Method on ControlClass
Generates a name based on the name of the underlying controlled class. Also updates the Control object's name attribute.

selfMatch Method on ControlClass
Makes sure that its name is set properly, based on the current name of the controlled object, then runs the normal selfMatch method.

Node: Unsorted, Next: , Previous: Core Classes, Up: Top

Unsorted

Node: Command Index, Next: , Previous: Unsorted, Up: Top

Command Index

Node: Method Index, Previous: Command Index, Up: Top

Method Index

Footnotes

  1. Yes, this is redundant, but there are parts of the internal code that only get to see the verb record, not the entire verbs structure

  2. this is equivalent to the end of the line entered by the user at this time

  3. Currently isn't implemented as a verb; this needs to be fixed.