How to Script

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Caution.png
Read This First

Unless you are playing in The Fallen, scripting while unresponsive, regardless of your status at the keyboard, is against the rules. It is your responsibility to create scripts that will not continue endlessly, in case you fall asleep or have to leave the keyboard suddenly.
This is not a trivial matter and can result in experience penalties, character loss, or permanent lockout.
In game type "NEWS 5 17" to review DR scripting policy.

You have been warned.


The Basics

The section will cover the most basic tools for scripting in the eScape and StormFront FEs.

Important Notes

  • Empty space before a command is ignored.
  • Empty lines are ignored.
  • If the end of the script is reached, the script exits.
  • All commands are case insensitive, though variables are not.
  • Only one command can be put on a line.

Simple Commands

  • # : Used for commenting, any line that begins with the number symbol is ignored by the script.
  • PUT <string>: This will cause the script to enter the string as if you typed it into the game and hit enter.
  • MOVE <string>: This will do the same thing as PUT, but will then pause the script until a new room is entered.
  • WAIT: This command will pause the script until a prompt is received. It is not affected by suppressing prompts in game.
  • WAITFOR <string>: This will pause the script until it sees the string.
  • WAITFORRE <string>: Same as WAITFOR but allows the use of Regular Expressions. See the advanced section for more details.
  • NEXTROOM: This will cause the script to wait until you enter a new room.
  • PAUSE <#>: This will pause the script for the indicated number of seconds.
  • SAVE: This command is obsolete and will not be covered. See Variables section for the function that replaced it.
  • EXIT: This will end the script.

Labels

Labels are basically like signposts that you can cause the script to jump to. The most common way to cause a script to switch to a label is using "GOTO <label>" although MATCH/MATCHRE is another way.

A label is placed but putting a word on it's own line, followed by a colon, such as

thisIsALabel:

Labels are not case sensitive, so "Label" is the same as "label" is the same as "lAbEl".

Matches

The combined use of MATCH, MATCHRE and MATCHWAIT are essential tools for the majority of intermediate and advanced scripts.

The MATCH command is executed with two parts, the label and the match string, in the form of "MATCH <label> <string>". If the <string> is found, the script will immedately jump to the specified label.

Here's an example pulled from a real script (note: the numbers are the line numbers and are not part of the script):

1	putAway:
2	MATCH putAway ...wait
3	MATCH cycle Stow what?
4	MATCH cycle You are already wearing that.
5	MATCH cycle But that is already in your inventory.
6	MATCH cycle You
7	PUT stow my pickle
8	MATCHWAIT

The combination of lines one and two illustrate the most common use for for MATCH. If the game pops up "...wait x seconds" when you attempt a command, it will cycle back to the label on line one and attempt it again.

Lines 3-6 watch for the various outcomes of the command on 7, and will jump to the specified label upon detecting them. The fact that the label is the same regardless of the outcome is not important since any number of labels can be mixed.

Lastly, line 8 is a special command that tells the script "wait here until a match is found". This can either be desirable, such as if you're waiting for the barge and don't want to do anything till it shows up, or can be undesirable, such as when your action produces a result you didn't put in a MATCH for and will wait forever.

MATCHRE allows use of Regular Expressions in the search string. See the advanced section for details on regular expressions.

Variables

Variables are basically storage locations for words. They allow you to imput information in one place and retreive it at another. They are refered to using the syntax "%<variable name>" such as "%target" or "%person". Note: Unlike labels, variables are case sensitive; "%variable" is NOT the same as "%Variable" or "%vArIaBlE".

There are two main types of variables, and one special one.

Command Line Variables

The first type is called a command line variable. When you start your script using the ".<scriptname>" method, after the name you can input up to 9 other words for storage. Example:

	.kill him andHim andHimToo her monkey randomGuy

These are then able to be accessed by the script. They are accessed using "%0" through "%9", with "%1" being the first word after the script name, "%2" being the second, etc. Note that "%0" is the same as putting "%1 %2 %3 %4 %5" .... "%9", listing out all the command line variables.

If you want to use multiple words as a single variable, there are two ways to do this.

  • word_word_word
  • "word word word"

Unfortunately, command line variables cannot be changed once the script is started, with a few exceptions, the major one being SHIFT. Upon encountering SHIFT, "%1" is deleted, and the rest is shifted down one, with "%2" now being "%1", "%3" being "%2", all the way to "%9" which is now empty.

How are these useful? Perhaps you wish to write a script that picks and disarms a box for you, however your box can be a crate, a strongbox, a box or even a coffer. Using "%1" in the proper place, you can run your script with ".pick coffer" and it will target your coffer for opening.

Note: These variables are deleted if the script ends for any reason.

It should be noted that if more than 9 variables are used, the program will store them, but they will be unavailable without use of the SHIFT command. For example, if you do include a tenth variable, the first SHIFT will cause it to become "%9".

Standard Variables

These variables are a different sort, because they can both be accessed from within the script and because they will remain after the script ends. However, unlike command line variables, they can only be altered by a script or through the Variables panel. Like all variables, they take the form of "%<variable name>".

There are two major script commands for interacting with standard variables. The first is SETVARIABLE, which uses the syntax "SETVARIABLE <variable name without the %> <variable contents>" such as "SETVARIABLE weapon sword". One thing to realize is that you can set a variable to nothing, by using "SETVARIABLE <variable name>", which can be useful in some advanced scripting.

The second way to interact with them is using DELETEVARIABLE, which does what you'd expect: it removes the variable and it's contents.

It is important to distinguish between an empty variable and a deleted variable. An empty variable when you call it, simply adds a blank space, but a deleted variable will insert the variable name when called. Example:

Command:

PUT pick coffer %way

Empty:

Result: pick coffer
This will end up picking your coffer normally

Deleted:

Result: pick coffer %way
This will result in the game telling you it cannot find your "coffer %way".

Counter Variable

There is a variable that is exclusively used for the COUNTER commands, "%c". See the section on COUNTER for more details.

Counter

The counter command provides the ability to do simple math and store the outcome to a variable. You are able to use the counter command in the following ways.

COUNTER ( SET | ADD | SUBTRACT | MULTIPLY | DIVIDE ).

The ability to do simple math and store the the value for use later opens up some great possibilities for your scripts.

The counter value itself is stored in the %c variable.

Counter Commands

SET:

The SET command allows you to set the %c variable to whatever number (or another variable holding a number)
1     COUNTER SET 52
2     ECHO the counter is %c

ADD:

The ADD command allows you to add a specified number (or variable containing a number) to the current counter value.
1     COUNTER SET 52
2     ECHO the counter is %c
3     COUNTER ADD 10
4     ECHO the counter is %c

SUBTRACT:

The SUBTRACT command allows you to subtract a specified number (or variable containing a number) from the current counter value.
1     COUNTER SET 52
2     ECHO the counter is %c
3     COUNTER SUBTRACT 10
4     ECHO the counter is %c

MULTIPLY:

The MULTIPLY command allows you to multiple the current counter value by a specified number (or variable containing a number).
1     COUNTER SET 52
2     ECHO the counter is %c
3     COUNTER MULTIPLY 10
4     ECHO the counter is %c

DIVIDE:

The DIVIDE command allows you to divide the current counter value by a specified number (or variable containing a number).
1     COUNTER SET 52
2     ECHO the counter is %c
3     COUNTER DIVIDE 10
4     ECHO the counter is %c

It should be noted that StormFront does not handle decimals at all, and they are simply truncated (rounded down to the nearest whole number).

Multiple Counters

The scripting engine itself does not allow you to have multiple counter variables going at once, there is however a way to get around this. Since the engine allows you to store one variable to another, and also allows you to set the current value of the counter you are able to preform a little coding magic, and give yourself multiple counters to work with.

The example below takes use of the fact you can set the counter to another variable(provided its a number), then do your math on it, and then store its value back to the original variable. Essentially this allows you to have as many counters going on as your heart desires.

1      SETVARIABLE MyCounter1 10
2      SETVARIABLE MyCounter2 20
3     
4      ECHO MyCounter1 is %MyCounter1
5      ECHO MyCounter2 is %MyCounter2
6     
7      COUNTER SET %MyCounter1
8      ECHO the counter is currently %c
9      COUNTER ADD 5
10     ECHO the counter is currently %c
11     SETVARIABLE MyCounter1 %c
12     
13     COUNTER SET %MyCounter2
14     ECHO the counter is currently %c
15     COUNTER ADD 5
16     ECHO the counter is currently %c
17     SETVARIABLE MyCounter2 %c
18     
19     ECHO MyCounter1 is %MyCounter1
20     ECHO MyCounter2 is %MyCounter2