MPI Reference Manual for FBMuck 6.00

by Revar Desmera <revar@belfry.com>


List of Topics by Category

You can get more help on the following topics:


Alphabetical List of Topics

Symbols

  &arg     &cmd     &how  

A's

  abs     add     and     attr     awake  

B's

  bless  

C's

  center     commas     comments     concat     contains     contents     controls  
  convsecs     convtime     count     created  

D's

  date     dbeq     debug     debugif     dec     default  
  definitions     delay     delprop     dice     dist     div  

E's

  eq     eval     eval!     exec     exec!     exits  

F's

  filter     flags     fold     for     force     foreach     ftime  
  fullname     func  

G's

  ge     gt  

H's

  holds  

I's

  idle     if     inc     index     index!     instr     isdbref     isnum  
  istype  

K's

  kill  

L's

  lastused     lcommon     le     left     lexec     links     list  
  listprops     lit     lmember     loc     locked     lrand     lremove  
  lsort     lt     ltimestr     lunion     lunique  

M's

  macros     max     midstr     min     mklist     mod     modified  
  money     muckname     muf     mult  

N's

  name     ne     nearby     nl     not     null  

O's

  online     ontime     or     otell     owner  

P's

  parse     pronouns     prop     prop!     propdir  

R's

  rand     ref     revoke     right  

S's

  secs     select     set     sign     smatch     stimestr     store  
  strip     strlen     sublist     subst     subt  

T's

  tell     testlock     time     timestr     timesub     tolower     toupper  
  type     tzoffset  

U's

  unbless     usecount  

V's

  v     version  

W's

  while     with  

X's

  xor  


Definitions and Details

  comments     definitions  


Comments:

Only 26 levels of recursion are allowed, so funcs that deep return literally. In loops, a max of 256 iterations are allowed before they exit automatically. Lists have a maximum size of 256 lines, or 4096 characters, whichever is less.

All matching will be done relative to the trigger object first, then relative to the triggering player, if nothing was matched in the first pass.

The 'me' and 'here' keywords always are relative to the triggering player. The trigger object is referred to by 'this'.


Definitions:

A Trigger object is the object that the MPI script is evaluated from.

A List is a string containing several individual substring items, seperated by carriage return characters.

A property based list is a set of consecutively numbered properties that each contain one string in a list of strings. Property based lists are often numbered like: listname1, listname2, listname3, listname4, &c. Another popular format is listname#/1, listname#/2, listname#/3, etc. MPI can read in either of those formats, and several more, for that matter.

For logical constructs, a string value of "0", or a null string ("") are both considered false. Any other value is considered true.


Time Functions

  convsecs     convtime     date     delay     ftime     kill     ltimestr  
  secs     stimestr     time     timestr     tzoffset  

{tzoffset}

Returns local time zone offset from GMT in seconds.


{time}
{time:timezone}

Returns a time string in the 24hr form hh:mm:ss. If the timezone argument is given, then it offsets the time returned by that number of seconds.


{date}
{date:timezone}

Returns a date string in the form mm/dd/yy. If the timezone argument is given, then it offsets the date returned by that number of seconds.


{ftime:format}
{ftime:format,tz}
{ftime:format,tz,secs}

Returns a time string in the format you specify. See 'man timefmt' for the %subs that you can use in the format string. If specified, tz is the number of seconds offset from GMT. If specified, secs is the systime to use, instead of the current time. {ftime:%x %X %Y,{tzoffset},0} will return the date and time for systime 0, for the local time zone of the server.


{timestr:secs}

Given a time period in seconds, this will return a concise abbreviated string representation of how long that time was. This might return a value like "9d 12:56" for 9 days, 12 hours, and 56 minutes.


{ltimestr:secs}

Given a time period, in seconds, this will return a string, including a breakdown of all the time units of that period. For example, given a number of seconds, it might return "1 week, 2 days, 10 mins, 52 secs".


{stimestr:secs}

Given a time period, in seconds, this will return the most significant time unit of that time period. For example, a number of seconds, that is equivalent to 9 days, 23 hours, 10 minutes, and 52 seconds, will be have the value "9d" returned, as the abbreviated most significant time unit.


{secs}

Returns system time: the number of second since midnight 1/1/70 GMT


{convtime:string}

Converts "HH:MM:SS Mo/Dy/Yr" format time string to systime seconds.


{convsecs:systime}

Converts systime seconds into a readable time string.


{delay:secs,expr}

Evaluates the given expression, then puts the result of that on the timequeue, to execute after the given number of seconds. At that time, the string is evaluated again, and displayed to the user, or to the room, depending on whether it was run from a regular message such as @succ, or from an omessage such as @osucc. Since the expression is evaluated both before and after being delayed, you need to put MPI code that is to run after the delay within a {lit:expr} command. If a {delay} evaluation is a null string, then the notify or notify_except will not be done. {delay} will return the process ID of the event it puts on the timequeue.


{kill:0}
{kill:processID}

Kills a process on the timequeue, that was possibly created by {DELAY}. If the process ID it is given is 0, then it will kill all processes done by that trigger object. If the process to be killed was not set off by that trigger, and was not set off by any object that the owner of the trigger owns, then this will error out with Permission denied. If no process is found, this returns 0. If a process was found, and the permissions were okay, then the process is killed, and {kill} returns the number of processes killed. Usually 1.


Logical Functions

  and     default     eq     ge     gt     if     le     lt  
  ne     not     or     xor  

{if:check,true}
{if:check,true,false}

This is a simple conditional command. It evaluates the 'check' argument and if it is true, then it evaluates the 'true' argument and returns it's result. If 'check' does not evaluate as true, then it will evaluate the 'false' argument, if there is one, and returns it's result. If there is no false argument, and 'check' evaluated false, then it returns a null string. Example:
    Your computer is {if:{eq:2,3},broken!,all right.}

Also see: not, and, or, xor, eq, ne, lt, gt, le, le, default and dbeq


{default:value1,value2}

Returns value2 if value1 is null or 0, otherwise returns value1. Example:
    You entered {default:{&arg},nothing}.


{eq:expr1,expr2}

If expr1 and expr2 evaluate out to the same value, then this returns true. Otherwise, this returns false. If both expressions evaluate out to numbers, then this compares them numerically.


{ne:expr1,expr2}

If expr1 and expr2 evaluate out to the same value, then this returns false. Otherwise, this returns true. If both expressions evaluate out to numbers, then this compares them numerically.


{gt:expr1,expr2}

Evaluates expr1 and expr2, then returns true if expr1 was larger.


{ge:expr1,expr2}

Evals expr1 and expr2, then returns true if expr1 was larger or equal.


{lt:expr1,expr2}

Evaluates expr1 and expr2, then returns true if expr1 was smaller.


{le:expr1,expr2}

Evals expr1 and expr2, then returns true if expr1 was smaller or equal.


{not:expr}

Returns the logical NOT of expr. If expr was true, this returns false. If expr was false, this returns true.


{or:expr1,expr2...}

Returns true if expr1 or expr2 evaluate as true. Otherwise, this returns false. If expr1 was true, this doesn't bother to exaluate expr2, as it does C-style shortcutting. If there are more than two arguments, then this will evaluate them until either one returns true, or until it has evaluated all the expressions. This returns false only if all of the expressions return false.


{and:expr1,expr2...}

Returns true if expr1 and expr2 evaluate as true. Otherwise, this returns false. If expr1 was false, this doesn't bother to evaluate expr2, as it does C-style shortcutting. If there are more than two arguments, then this will evaluate all of them until either one returns false, in which case this function returns false, or until it has evaluated all of the arguments. This function returns true only if all the arguments evaluate as true.


{xor:expr1,expr2}

Returns true if expr1 or expr2 evaluate as true, but false if both do. Otherwise, this returns false.


Property Handling

  bless     concat     delprop     exec     exec!     index     index!  
  lexec     list     listprops     prop     prop!     propdir     rand  
  select     store     timesub     unbless  

{prop:propname}
{prop:propname,obj}

Returns the literal string value of the given property. If no object parameter is passed to it, it looks for the property somewhere down the environment from the trigger object. Otherwise, it looks down the environment from the object specified. If the property is not found, this returns an empty string. If the property that it tries to access is read restricted and the owner of the trigger object does not own the object that the property is found on, then the MPI script stops with a Permission denied error.


{prop!:propname}
{prop!:propname,obj}

Returns the literal string value of the given property. If no object parameter is passed to it, it looks for the property on the trigger. Otherwise, it looks for the property on the object specified. If the property is not found, this returns an empty string. If the property that it tries to access is read restricted and the owner of the trigger object does not own the object that the property is found on, then the MPI script stops with a Permission denied error.


{exec:propname}
{exec:propname,obj}

Returns the string value of the given property, after having evaluated any embedded MPI commands that it contained. If no object parameter is passed to it, it looks for the property somewhere down the environment from the trigger object. Otherwise, it looks down the environment from the object specified. If the property is not found, this returns an empty string. If the property that it tries to access is read restricted and the owner of the trigger object does not own the object that the property is found on, then the MPI script stops with a Permission denied error.


{exec!:propname}
{exec!:propname,obj}

Returns the string value of the given property, after having evaluated any embedded MPI commands that it contained. If no object parameter is passed to it, it looks for the property on the trigger. Otherwise, it looks for the property on the object specified. If the property is not found, this returns an empty string. If the property that it tries to access is read restricted and the owner of the trigger object does not own the object that the property is found on, then the MPI script stops with a Permission denied error.


{index:propname}
{index:propname,obj}

Returns the string value of the property whose name is stored in the given property. This sounds confusing, but it's basically just the same as {exec:{prop:propname}}. If no object parameter is passed to it, it looks for both the index property and the referenced property somewhere down the environment from the trigger object. Otherwise, it looks down the environment from the object specified for both of them. If either property is not found, this returns an empty string. If the property that it tries to access is read restricted, and the owner of the trigger object does not own the object that the properties are found on, then the MPI script stops with a Permission denied error. Any MPI code in the target property is evaluated and the result is returned.


{index!:propname}
{index!:propname,obj}

Returns the string value of the property whose name is stored in the given property. This sounds confusing, but it's basically just the same as {exec!:{prop!:propname}}. If no object parameter is passed to it, it looks for both the index property and the referenced property on the trigger object. Otherwise, it looks on the specified object for both of them. If either property is not found, this returns an empty string. If the property that it tries to access is read restricted, and the owner of the trigger object does not own the object that the properties are found on, then the MPI script stops with a Permission denied error. Any MPI code in the target property is evaluated and the result is returned.


{store:val,prop}
{store:val,prop,obj}

Stores a string value in a given property. If no obj parameter is given, then it stores the property on the trigger object. Otherwise, it will store it on the given object. If you specify a propname that is protected, you will get a Permission Denied error. You are only allowed to store properties on objects controlled by the owner of the trigger object. The trigger object is the object that triggered the evaluation of the MPI commands. This function returns the string that is stored as the prop value. If you store a null value in the property, then it will remove the property if it is not a propdir. It will clear the value of the prop if it IS a propdir.


{delprop:propname}
{delprop:propname,object}

This function will remove a property and all of it's subsidiary properties in the case that it is a propdir. This will delete the property on the trigger object, unless an object argument is specified. If one is, then it will delete the property on that given object. This function returns a null string. If you specify a propname that is protected, you will get an error of Permission Denied. You are only allowed to delete properties from objects that are owned by the owner of the trigger object.


{bless:propname}
{bless:propname,object}

Blesses a property so that MPI executed from it will run with blessed permissions. This command itself requires blessed permissions to run.


{unbless:propname}
{unbless:propname,object}

Removes the blessing of a property so that MPI executed from it will no longer run with blessed permissions. This command itself requires blessed permissions to run.


{list:listname}
{list:listname,obj}

Returns a string, containing a carriage-return delimited list of individual lines from a property based list. A property based list is a series of properties that are consecutively numbered. The server understands several different formats, and can also read in property lists in either the propnameX format, or the propname#/X format. It does NOT evaluate the contents of the list for embedded MPI commands. If no obj argument is supplied, then it looks for the list somewhere down the environment from the trigger object. Otherwise, it looks for the list down the environment from the given object.


{concat:listname}
{concat:listname,obj}

Returns a string, containing the concatenated lines of a property based list. It concatenates the list semi-intelligently, putting a single space between lines normally, and two spaces between lines when the previous one ended with a period, exclamation mark, or question mark. A property based list is a series of properties that are consecutively numbered. The server understands several different formats, and can also read in property lists in either the propnameX format, or the propname#/X format. It does NOT evaluate the contents of the list for embedded MPI commands. If no obj argument is supplied, then it looks for the list somewhere down the environment from the trigger object. Otherwise, it looks for the list down the environment from the given object.


{lexec:listname}
{lexec:listname,obj}

This takes a property based list, and concatenates all its lines together, stripping spaces from the beginning and end of each one. It then evaluates the result for MPI commands, and returns the resulting string. A property based list is a series of properties that are consecutively numbered. The server understands several different formats, and can also read in property lists in either the propnameX format, or the propname#/X format. If no obj argument is supplied, then it looks for the list somewhere down the environment from the trigger object. Otherwise, it looks for the list down the environment from the given object.


{rand:listname}
{rand:listname,obj}

Returns the value of a randomly picked list item from a property based list. If no obj parameter is given, then it looks down the environment from the trigger object for the list. Otherwise, it looks down the environment from the given object. Any MPI code in the target property is evaluated and the result is returned.


{select:value,listname}
{select:value,listname,object}

Returns the value of a single list item from a sparse property list. The item chosen is the one who's line number is the largest one that is less than or equal to the given value. If the list is missing any items, then {select} will return the item in the list with the highest line number that is less than or equal to the given value. ie: If the list has the following entries:
    _junk#/1:one
    _junk#/5:two
    _junk#/16:three
    _junk#/20:four
Then {select:9,_junk} will return "two", {select:16,_junk} will return "three", and {select:25,_junk} will return "four".


{timesub:period,offset,listname}
{timesub:period,offset,listname,object}

This is sort of like {list}, except that it will only return one line of the given named property list. The line it chooses depends on the time. Any MPI code in the target line is evaluated and the result is returned. The period is the length of time, in seconds, that it takes for {timesub} to cycle through the entire list. The offset is the number of seconds to offset into the time period, if you actually need to synchronize the {timesub} with something. The offset usually is just left at zero. If the object argument is not passed, it looks for the list on the trigger. What this all means, is that if you have, for example, a period of 3600 (one hour), an offset of zero, and a property list that has six items in it, then {timesub} will return the first line of the property list during the first ten minutes of the hour, the second line during the next ten minutes, and so on, until it returns the last line during the last ten minutes of the hour. Then it returns the first line for the beginning of the next hour. Here's an example:

{timesub:86400,0,_sunmoon} This example will show different property list lines, depending on the time of day. The period is 86400 seconds, which is one day. If the property list has 24 items in it, then a different line will be returned for each hour of the day.


{propdir:propname}
{propdir:propname,object}

Returns true if the given property is a propdir, containing sub-props. Otherwise, this returns false. If no object parameter is passed to it, it looks for the property on the trigger object. Otherwise, it looks on the object specified. If the property is not found, this returns false.


{listprops:propdir}
{listprops:propdir,object}
{listprops:propdir,object,pattern}

This function will return a list that contains the full names of all the sub-properties contained by the given propdir. If not given, object defaults to the trigger object. If a pattern is given, the sub-properties in the propdir are each compared against the smatch wildcard pattern, and only those that match are returned in the list. This comparison is only done on the last part of the property name after the last /.

Also see: propdir and smatch


String Functions

  attr     center     eval     eval!     instr     left     lit  
  midstr     nl     null     otell     pronouns     revoke     right  
  smatch     strip     strlen     subst     tell     tolower     toupper  
String functions generally don't strip spaces in their arguments.

{nl} or \r

Returns a carriage return character. This can be used to seperate items in a list, or can split the string at that point, starting a new line. Example: the string:
    This is\ran example{nl}of using newlines.
would print out like:
    This is
    an example
    of using newlines.


{subst:str,old,new}

Returns a copy of 'str' with all substring instances of 'old' replaced by the text specified by 'new'. Basically just substitutes the new text for the old text in str. example: {subst:Hello World!,l,r} would return "Herro Worrd!"


{strlen:string}

Returns an integer that is the number of character in string.


{smatch:str,pattern}

Matches 'str' against the wildcard pattern. If there is a match, this returns true, or "1". If it doesn't match, this returns a value of "0", or false. In wildcard patterns, the following characters have the following meanings:
    *               matches any number of any character.
    ?               matches one character, of any type.
    [abcde]         matches one char, if it is a, b, c, d, or e.
    [a-z]           matches one char, if it is between a and z, inclusive.
    [^abd-z]        matches one char is it is NOT a, b, or between d and z.
    {word1|word2}   matches one word, if it is word1, or word2.
    {^word1|word2}  matches one word, if it is NOT word1 or word2.
    \               escapes any of the prev chars, making it not special.


{strip:string}

Returns a copy of string with all the spaces stripped from the beginning and the end.


{tolower:string}

Returns a copy of string, with all uppercase chars converted to lowercase.


{toupper:string}

Returns a copy of string, with all lowercase chars converted to uppercase.


{right:string}
{right:string,fieldwidth}
{right:string,fieldwidth,padstring}

Takes a string and pads it to fit the given fieldwidth, with the string right justified. If no padstring is given, it assumes that it will pad the string with spaces. If no fieldwidth is given, it assumes that the field width is 78 characters. Example:
    {right:Hello,10,_.}
would return the string "_._._Hello"


{left:string}
{left:string,fieldwidth}
{left:string,fieldwidth,padstring}

Takes a string and pads it to fit the given fieldwidth, with the string left justified. If no padstring is given, it assumes that it will pad the string with spaces. If no fieldwidth is given, it assumes that the field width is 78 characters. Example:
    {left:Hello,10,_.}
would return the string "Hello_._._"


{center:string}
{center:string,fieldwidth}
{center:string,fieldwidth,padstring}

Takes a string and pads it to fit the given fieldwidth, with the string center justified. If no padstring is given, it assumes that it will pad the string with spaces. If no fieldwidth is given, it assumes that the field width is 78 characters. Example:
    {center:Hello,10,1234567890}
would return the string "123Hello12"


{instr:str1,str2}

Lists the position of the first substring within str1 that matches str2. If no such substring exists, then this returns a 0.


{midstr:str,pos}
{midstr:str,pos1,pos2}

Returns the substring that starts at pos1 within str. If no pos2 is given, then the returned string is only the character at the given pos1 position. if a pos2 position is given, then it returns the substring beginning at pos1 and ending at pos2, inclusive. If pos1 or pos2 are negative, then they represent the position that is that absolute number of characters from the end of the string. The first character in str is 1, and the last one can always be referenced by -1. If a position would be before the beginning of the string, it is assumed to be at the beginning of the string. If it would be beyond the end of the string, it is assumed to be at the last character. If the starting position is later in the string than the ending position, then the returned string has the characters in reverse order. If either pos1 or pos2 are 0, then this returns a null string. ("")


{lit:string}

Returns the literal string given as its parameter. This means you can have things that look like MPI commands within it, and it will not evaluate them, but will rather just treat them as a string.


{eval:string}

Sort of the exact opposite of {lit:}. This takes a string, and evaluates it for MPI commands embedded within it. This can be used on the output of {list:}, for example. The evaluated mpi commands will be run unblessed.

Also see: eval!


{eval!:string}

Sort of the exact opposite of {lit:}. This takes a string, and evaluates it for MPI commands embedded within it. This can be used on the output of {list:}, for example. Unlike the {eval} command, the evaluated mpi commands will be run with the same blessings as the code that executed the {eval!}.

Also see: eval and revoke


{revoke:commands}

Executes the enclosed commands with all blessing permissions revoked. This is good to wrap around {eval} statements that may execute user supplied code, to prevent security holes.


{null:expr...}

Returns a null string, no matter what the expressions within it return. This can take up to nine arguments, though you could pass the output of several commands as one argument.


{pronouns:string}
{pronouns:string,object}

If passed one argument, evaluates the string and does pronoun substitution with regards to the using player. If given two args, it does the pronoun substitution with regards to the given object.


{tell:string}
{tell:string,player}

If passed only a string, tells the user that string. If passed both a string, and a player dbref, it will tell the given player the message. This returns the message that was sent. If the trigger isn't a room, or an exit on a room, and if the message doesn't already begin with the user's name, then the user's name will be prepended to the message. The two exceptions to this are that if the messages is being sent to the owner of the trigger, or to the user, then the user's name will not be prepended.


{otell:string}
{otell:string,room}
{otell:string,room,player}

This will tell the given string to all the players in the room, except for the given player. If no room argument is given, it is assumed to be the room that the triggering player is in. If no player is given, then it assumes that you want to skip sending the message to the triggering player. If you pass it a player of #-1, it will send the message to all the players in the room. This returns the message that was sent. If the trigger isn't a room, or an exit on a room, and if the message doesn't already begin with the user's name, then the user's name will be prepended to the message.


{attr:attribute,string}
{attr:attribute,attribute,string}
{attr:attribute,...,attribute,string}

This will surround the given string with the neccesary ANSI escape codes to cause the text to display with the given attributes. You may specify up to eight attributes, though this shouldn't ever be neccesary. The supported attributes are: null, reset, bold, dim, flash, underline, reverse, black, red, yellow, green, cyan, blue, magenta, white, bg_black, bg_red, bg_yellow, bg_green, bg_cyan, bg_blue, bg_magenta, and bg_white.

Not all clients will display all these attributes, and those that do won't always show them the same way. Players who do not have their Color flag set will not see the ANSI codes or colors at all. Nesting {attr} commands probably just won't work.


Math Functions

  abs     add     dec     dice     dist     div     inc     max     min     mod     mult     sign     subt  
All math functions deal with integer numbers.

{inc:var}
{inc:var,val}

Increments the value of the given variable by one, returning the result. If a value argument is given, then it will add that value to the variable, instead of the value 1.


{dec:var}
{dec:var,val}

Decrements the value of the given variable by one, returning the result. If a value argument is given, then it will subtract that from the variable, instead of the value 1.


{add:expr1,expr2}
{add:expr1,expr2,expr3...}

Returns the sum of the values of expr1 and expr2. If more than two args are given, then this will add all the args together and return the result.


{subt:expr1,expr2}
{subt:expr1,expr2,expr3...}

Returns the difference of the values expr1 and expr2. If more than two args are given, all values are subtracted from the first value in sequence. For example: {subt:10,3,2,4} would be read as 10 - 3 - 2 - 4, and it would return a result of 1.


{mult:expr1,expr2}
{mult:expr1,expr2,expr3...}

Returns the product of the values expr1 and expr2. If more than two args are given, then they are all multiplied together to get the result.


{div:expr1,expr2}
{div:expr1,expr2,expr3...}

Returns the value of expr1 divided by expr2. Division by zero will return zero. If more than two arguments are given, then the first argument is divided by the second, and the result is divided by the third, etc, for all of the arguments. For example: {div:180,6,3,5} would be read like 180 / 6 / 3 / 5, and a result of 2 would be returned.


{mod:expr1,expr2}

Returns the leftover remainder of expr1 divided by expr2. If more than two arguments are given, then the first arguments is modded by the second, then the result of that would be modded by the third, and so on and so forth. For example: {mod:91,20,3} would be read as 91 % 20 % 3, and a result of 2 would be returned.


{dice:X}
{dice:X,Y}
{dice:X,Y,Z}

Given one parameter, picks a random number between 1 and X. (1dX) Given two parameters, it randomly generates Y numbers between 1 and X, and adds them together. (YdX) A third parameter, if given, is just added to this sum as a modifier. (YdX+Z)


{min:expr1,expr2}

Returns the lesser of the values of expr1 and expr2.


{max:expr1,expr2}

Returns the greater of the values of expr1 and expr2.


{abs:expr}

Returns the absolute value of expr.


{sign:expr}

Returns -1 if expr is negative. Returns 1 if expr is positive. If expr is 0, then it returns 0.


{dist:x,y} Returns distance from 0,0 that x,y is.
{dist:x,y,z} Returns distance from 0,0,0 that x,y,z is.
{dist:x,y,x2,y2} Returns distance between x,y and x2,y2.
{dist:x,y,z,x2,y2,z2} Returns distance between x,y,z and x2,y2,z2.

Given two arguments, this calculates the distance of a 2D point from the origin. Given three arguments, this calculates the distance of a 3D point from the origin. Given four arguments, this calculates the distance between a pair of 2D points. Given six arguments, this calculates the distance between a pair of 3D points.


Looping Functions

  filter     fold     for     foreach     parse     while  

{for:varname,start,end,increment,command}

Acts as a counting loop, like BASIC's for loops. The varname is the name of the variable that it will create and use to store the count value. The start value will be the initial value of the variable, and the end value will be the value that the variable is working towards. The increment is how much the variable will be incremented by in each loop. The command will be eval- uated for each value of the variable between the beginning and ending values. For example:
    {null:{for:i,10,1,-1,{tell:{&i}}}}
will echo a countdown from ten to one, inclusive, to the user.


{while:check,expr}

This is a looping structure. It evaluates the 'check' argument, and if it evaluates true, then it evaluates the expr argument, and repeats the process. If 'check' evaluates false, then the loop is exited. This returns the result of the last evaluation of expr.


{foreach:var,list,expr}
{foreach:var,list,expr,sep}

This evaluates expr for each and every item in the given list. On each evaluation, the temporary variable var will contain the value of the item under scrutiny. var will only be defined for the duration of expr, and will be undefined after the {foreach} construct finishes. If sep is given, then it uses that string as the item seperator in list, instead of the usual carriage return character. sep can be multiple characters long. This structure returns the result of the last evaluation of expr. Example:
    {foreach:thing,{contents:here},{tell:{name:{&thing}}}}
This will display the name of every object in the room, then it will return the name of the last object it displayed.


{filter:var,list,expr}
{filter:var,list,exp,sep}
{filter:var,lst,exp,sep,s2}

This evaluates expr for each and every item in the given list. On each evaluation, the temporary variable var will contain the value of the item under scrutiny. This function returns a list containing all of the items from the input list, for which expr evaluated true. var will only be defined for the duration of expr, and will be undefined after the {filter} construct finishes. If sep is given, then it uses that string as the item seperator in the input list, instead of the usual carriage return character. If s2 is defined, then it will use that string to seperate the items in the list it returns, instead of the normal carriage return. sep and s2 can be multiple characters long.


{parse:var,list,expr}
{parse:var,list,expr,sep}
{parse:var,list,expr,sep,s2}

This evaluates expr for each and every item in the given list. On each evaluation, the temporary variable var will contain the value of the item under scrutiny. This function returns a list containing the output of expr for each item within the list. This lets you do direct translat- ion of a list of dbrefs, for example, into a list of names. var will only be defined for the duration of expr, and will be undefined after the {filter} construct finishes. If sep is given, then it uses that string as the item seperator in the input list, instead of the usual carriage return character. If s2 is defined, then it will use that string to seperate the items in the list it returns, instead of the normal carriage return. sep and s2 can be multiple characters long.


{fold:var1,var2,list,expr}
{fold:var1,var2,lst,expr,sep}

This takes a list and stores the first two items in var1 and var2, then evaluates expr. The value returned by expr is then put in var1, and the next list item is put in var2. Expr keeps being evaluated in this way until there are no more list items left. This returns the last value returned by expr. If a sep argument is given, the input list is assumed to have its individual items delimited by that string, otherwise it assumes a carriage return.


Database Related Functions

  contains     contents     controls     created     dbeq     exits     flags  
  force     fullname     holds     istype     lastused     links     loc  
  locked     modified     money     name     nearby     owner     ref  
  testlock     type     usecount  

{ref:obj}

Returns the dbref of the given object in the form #xxxx. The object must be in the vicinity, or controlled by the owner of the trigger object.


{name:obj}

Returns the name of the given object. If the object is an exit, the name returned is the first exit name it has before the first ';'. The object must be in the vicinity, or controlled by the owner of the trigger object.


{fullname:obj}

Returns the name of the given object. In the case where the object is an exit, then the full name of the exit is given, including all the ; aliases. The object must be in the immediate vicinity, or be controlled by the owner of the trigger object.


{owner:obj}

Returns the owner of the given object. The object must be in the vicinity, or be controlled by the trigger object's owner.


{loc:obj}

Returns the location of the given object. The object must either be in the vicinity, or it must be controlled by the owner of the trigger object.


{flags:obj}

Returns a flaglist string from obj. ie: PM2J. The object must either be in the vicinity, or it must be controlled by the owner of the trigger object.


{created:obj}

Returns the time and date that obj was created. The number returned is suitable for use with {convsecs}.


{modified:obj}

Returns the time and date that obj was last modified. The number returned is suitable for use with {convsecs}.


{lastused:obj}

Returns the time and date that obj was last used. The number returned is suitable for use with {convsecs}.


{usecount:obj}

Returns the usage count that obj has incurred since it was created.


{controls:obj}
{controls:obj,player}

If one argument is given, then this returns true ("1") if the trigger object's owner controls the given object. If two arguments are given, then it returns true if the given player controls the given object. Otherwise, this returns false. ("0") Wizards control everything.


{nearby:obj}
{nearby:obj,obj2}

If one argument is given, then this returns true ("1") if the given object is nearby to the trigger object. If two arguments are given, then it returns true if the two objects are nearby one another. Otherwise, this returns false. ("0") Nearby is defined as: 1) The two objects are in the same location, or 2) One object contains the other, or 3) the two objects are in fact the same object.


{money:obj}

This returns the value of an object of TYPE_THING, or returns how many pennies a player has.


{type:obj}

Returns the type of an object. The possible values are: Bad, Room, Exit, Thing, Player, and Program.


{istype:obj,typ}

Returns true if the given object if of the given type. Valid types are: Bad, Room, Exit, Thing, Player, and Program.


{contents:obj}
{contents:obj,type}

Returns a list of the contents of the given object. If a second argument is passed to it, it restricts the listing to only those objects that are of the given type. Either the object must be nearby the trigger object, or else the owner of the trigger object must control the object. Otherwise this will error out with a Permission Denied error. The valid object type values are Room, Thing, Exit, Player, Program, and Bad. HINT: If you need to get a list of two types of objects from the room, just concatenate the lists from two calls to this function, with each object type you want. ie:
    {mklist:{contents:here,player},{contents:here,thing}}    or
    {contents:here,player}{nl}{contents:here,thing}


{exits:obj}

Returns a list of all the exits on the given object. The owner of the trigger object has to control obj, or else this errors out with Permission Denied. Programs and exits never have exits attached to them.


{links:obj}

Returns the object reference of what the given object if linked to. Since exits can be meta-links, linked to multiple exits, if there is more than one link, then this function returns a list of all the destinations, seperated by carriage return characters. (\r)


{force:object,command}

Forces the given player or thing to do the given command. The thing forced must be @flock'ed to the trigger object, or the trigger object's owner, and it must be set XFORCIBLE, or else this function will get a Permission Denied error. This function returns a null string. {Force} cannot force a thing-object to do something, if it is set Dark, is in a room set Zombie, or is owned by a player set Zombie.


{dbeq:obj1,obj2}

Returns true if obj1 and obj2 refer to the same object. This does name matching, so {dbeq:*Wizard,#1} will return true if #1 is named Wizard.


{locked:player,obj}

Tests the _/lok (@lock) standard lock property on obj against the given player. Returns true if the lock is locked against the player.


{testlock:obj,prop}
{testlock:obj,prop,who}
{testlock:obj,prop,who,def}

Tests the lock property 'prop', on 'obj' against the given player 'who'. If no 'who' argument is given, then it checks the lock against the using player. If a def argument is given, then the lock will default to that value, if there is no lock property of the given name on the given object. Returns true if the lock is locked against the player.


{holds:obj1}
{holds:obj1,obj2}

Returns true if the location of obj1 is obj2. If no obj2 argument is given, then this will return true if the location of obj1 is the player.


{contains:obj1}
{contains:obj1,obj2}

Returns true if obj1 is within obj2, or within anything it contains, or within anything they contain. If obj2 is not given, then it checks to see is obj1 is held by the player, or by anything they hold, etc. Basically, this just sees if obj1 is within the locational environment of obj2.


Connection Related Functions

  awake     idle     online     ontime  

{online}

Returns a list of players who are online. This function can only be executed with blessed permissions.


{awake:player}

Returns how many times player is connected. This means that it will returns 0 if the player is not connected. If the given object is NOT a player, it will return 0. If the given player is NOT local to the trigger, and is not the owner of the trigger, and this is not run with blessed perms, then this will return 0. In all other cases, it will return a positive number, being how many times the given player is connected to the server.


{ontime:player}

Returns player online time in seconds. If the given player is not connected, or is not a player object at all, then this will return -1. This returns the online time for the most recently connected connection, if there are multiple connects.


{idle:player}

Returns player idle time in seconds. If the given player is not connected, or is not a player object at all, then this will return -1. This returns the idle time for the most recently connected connection, if there are multiple connects.


Variable Handling Functions

  &arg     &cmd     &how     set     v     with  

{&VAR}
{v:VAR}

These are two ways of trying to do the same thing. They return the value of the named variable VAR. If there is no variable with the given name currently defined, then this gives an error stating as much. Variables can be defined either with the {with:} function or within a looping command.

There are three standard variables that every MPI program can read:


{&how}

The {&how} variable is a short string telling what ran the MPI command. It can have the values "(@desc)", "(@succ)", "(@osucc)", etc. for when it is run from an @desc, an @succ, an @osucc, or whatever. It can also have the value "(@lock)" for when it is run from a lock test.


{&cmd}

The {&cmd} variable contains the command name the user used, that caused the MPI to run. This is generally the exit name that the player triggered. For example, if the player typed 'east', and triggered the exit named 'east;e;out', which ran some MPI commands, the {&cmd} variable would have a value of "east".


{&arg}

The {&arg} variable contains a string with the value of the command line arguments the user entered. This is so that you can have stuff like MPI in the fail of an exit, and when the user triggers the exit, and has some extra text on the line they entered, other than the exitname, the MPI can take that extra stuff as arguments for use. Note that you need to set an action HAVEN to get it to accept command line arguments.

Other MPI functions used to work with variables are:


{set:var,value}

This sets the value of the given named variable to the given value. If no variable with that given name is currently defined, then this gives an error message complaining about that.


{with:var,val,expr..}

This defines a new variable with the given name, and sets it's value to the given val. Up to 7 expr's are allowed, but the only value returned to {with}'s caller, is the value returned by the evaluation of the last expr. If there is already a variable of the same name, then this command will override that variable, for the duration of the {with:} command. The new variable is only valid to use within the confines of the {with:} command, and it will go away after the command completes. This provides scoped variables quite effectively. NOTE: There can be no more than 32 variables defined at any one time, total. This includes variables that are defined within macros, or properties or lists that are executed with {exec:} or {lexec:}. Here's an example to illustrate the scope of variables inside of {with:} commands:
    {prop:_mydesc}                           <- {&people} not defined.
    {with:people,{contents:here,players},    <- Defining.  Not available yet.
        {if:{count:{&people}},               <- It's usable now.
            The players awake here are
            {lit: }                          <- just puts in a space.
            {commas:{&people},{lit: and },
                who,{name:{&who}}            <- uses {&who} as temp var.
            }                                <- {&who} no longer defined.
        }
    }                                        <- {&people} no longer defined.


List Handling Functions

  commas     count     lcommon     lmember     lrand     lremove     lsort     lunion  
  lunique     mklist     sublist  

{count:list}
{count:list,sep}

This counts the number of \r delimited items that are in the given list. This is effectively a list item count. If the sep argument if given, then it counts the number of sep delimited substrings in list. ie: The default sep is \r. (A carriage return.)


{mklist:value...} Returns a list with all given values.

This returns a list with all the given values as list items, seperated by carriage returns. ('\r's) Example:
    {mklist:Tom,Dick,Harry}
returns "Tom\rDick\rHarry". Note: A maximum of nine items can be passed to the {mklist} function. If you need more, you can chain {mklist}s together. Example:
    {mklist:{mklist:a,b,c,d,e,f,g,h,i},j,k,l,m,n,o,p}


{sublist:list,pos1}
{sublist:list,pos1,pos2}
{sublist:list,pos1,pos2,sep}

Takes a list, and returns a subset of the list items within it. The subset is all the list items between list item pos1, and list item pos2, inclusive. If the pos2 argument is omitted, it assumes that pos2 is the same as pos1. If pos2 is less than pos1, then all the list items between pos2 and pos1 are returned, in reversed order. If pos1 or pos2 are negative, it counts that many list items back from the end of the list, so -1 is the last list item, and -5 would be the fifth from last list item. The input list is assumed to be delimited by carriage returns (\r) unless the sep argument is given.


{lrand:list}
{lrand:list,seperator}

Returns a randomly picked stringlist item from the given list. If the seperator argument is given, then it will assume that the stringlist has it's items delimited by the given seperator string, instead of by carriage returns.


{lunique:list}

Returns list with all duplicate items removed.


{lunion:list1,list2}

Combines the contents of list1 and list2, removing any duplicates.


{lcommon:list1,list2}

Creates a list containing every item that appears in BOTH list1 and list2. Any duplicate items in the resulting list are removed.


{lremove:list1,list2}

Returns the contents of list1, with any items that match an item in list2 removed. The resulting list has all duplicate items removed.


{lmember:list,item}
{lmember:list,item,delimiter}

Returns 0 if the given item is NOT in the given list, otherwise, it returns the item's position in the list. The first list item in the list would return 1, and the third would return 3, for example. If the delimiter argument is given, then it treats the list as if it were delimited by that string, instead of by carriage returns. (\r's) Example:
    {lmember:{mklist:a,b,c,d,e,f},d}
would return 4.


{lsort:list}
{lsort:list,var1,var2,expr}

Returns the sorted contents of list. If 4 arguments are given, then it evaluates expr with a pair of values, in var1 and var2. If expr returns true, then it will swap the positions of the two values in the list. It runs this comparison on every pair of items in the list, so it will be evaluated N*N times, where N is the number of items in the list. This method can also be used to randomize a list. Example:
    {lsort:{&list},v1,v2,{gt:{dice:100},50}}


{commas:list}
{commas:list,lastsep}
{commas:list,lastsep,var,expr}

Takes a list and returns a plain english comma delimited string with the items in it. For example, {commas:{mklist:Tom,Dick,Harry}} will return "Tom, Dick and Harry". If you specify the lastsep argument, you can replace the "and" with something else, such as "or" to get a result like "a, b or c". Note: You need to be careful to include spaces around the "or" or else you might get a result like "a, borc". Example:
    {commas:{mklist:a,b,c}, or }
If the var and expr arguments are passed, then for every item in the list, it will set the value of the given variable name (which it will declare) to the item, then evaluate expr, and use the result in the string it outputs. Example:
    {commas:{contents:here},\, or ,v,{name:{&v}}}
will return the name of every object in the room in a comma separated list, using ", or " as the final conjunction. ie: "Tom, Can of SPAM, Dick, or Harry."


Miscellaneous Functions

  debug     debugif     isdbref     isnum     muckname     muf     version  

{isnum:number}

Returns true if the string passed to it is a valid number.


{isdbref:dbref}

Returns true if the string passed to it is a valid dbref.


{version}

Returns the version string for the server.


{muckname}

Returns the muck name string. For example, it might return: "FurryMUCK"


{muf:prog,arg}

Runs the given MUF prog with the string arg on the stack. This returns the top stack value when the prog exits. If the MPI code was run from a propqueue like _listen, or _connect, then {muf} cannot run a MUF program with a mucker level of less than 3


{debug:expr}

This will show MPI debugging information for all the commands within the given expression. This is useful for seeing why something isn't working. This returns the result of the evaluation of expr.

Also see: debugif


{debugif:cond,expr}

This will evaluate the conditional cond, and, if the result is true, (not an empty string, and not 0), then this will show MPI debugging info for all the commands within the given expression. If cond evaluated as false, then expr is evaluated without the debugging info being displayed. This is useful for Debugging code selectively. This returns the result of the evaluation of expr. Example:
    {parse:v,{contents:here},{debugif:{dbeq:{&v},me},{dostuff:{&v}}}}
to only debug the running of the command {dostuff} when the argument will be the player who is running the MPI.

Also see: debug and if


Macros and Functions

  func     macros  

Macros:

If the MPI interpreter comes across a function name that it does not recognize, it will look in the _msgmacs/ propdirs down the environment from the trigger object, for a property with the name of the function. If it does find it there, then it takes the value of that property, and substitutes it in for the function as a macro. The arguments to the function replace the {:1} through {:9} markers in the macro definition. For example, if there were a property set on #0, defined as:
    _msgmacs/div_rand:{add:{div:{:2},10},{dice:{:1}}}
And you had some MPI code that looked like:
    {div_rand:22,160}
Then the macro would expand out to:
    {add:{div:160,10},{dice:22}}
After the macro argment substitution is complete, it is then evaluated.


{func:name,vars...,def}

This effectively defines a function in MPI, with the given name, that takes the given named variables. The function is not immediately evaluated, so it needs to be invoked later, to do anything. Here's an example:

    {func:sqr,val,{mult:{&val},{&val}}}

This defines the function 'sqr', that takes a single argument. That argument is stored in the 'val' variable. The function will multiply the value of the number passed to it, by itself, returning the result. It's invoked like:

    {sqr:10}

Effectively, the above {func} declaration is the same as the following macro, and in fact, it's internally handled the same way:

    _msgmacs/sqr:{with:val,{:1},{mult:{&val},{&val}}}

You can define a function that takes more than one argument, but the maximum number of args you can pass to the function is seven. Example of multiple arguments:

    {func:names,list,numsp,flagsp,
        {parse:v,{&list},
            {name:{&v}}
            {if:{or:{&numsp},{&flagsp}},
                {lit:(}
                {if:{&numsp},{ref:{&v}}}
                {if:{&flagsp},{flags:{&v}}}
                {lit:)}
            }
        }
    }
    {names:{contents:here},1,1}