Inform 7

[ Home ] [ Up ] [ Writing Process ] [ Adrift ] [ Inform 7 ] [ Description ] [ Narration ] [ Exposition ]

        

This set of instructions can help students learn a useful subset of Inform 7.

 

Getting Started With Inform 7

 

            Inform 7 is an extremely powerful tool for writing interactive stories.  Unlike similar tools, Inform 7 uses a form of 
"natural language."  In other words, it allows a writer to create a work of interactive fiction by writing somewhat normal 
English sentences.  However, the writer must follow a rather strict set of rules in creating sentences that will really lead 
to an interactive story.

 

I.         Set Up Your Project

A. Start Inform 7.

B. From the list of choices that appears, choose "Start a New Project."

C. Choose the directory for your project by clicking on the button with three dots on it.  This button appears on the right side of 
your screen.

D. From the list of drives and directories that appears, choose the directory you want to use to store your project, and then 
click on OK.

E. In the appropriate box, type the name of your project, which should be the title of your interactive story.

F. In the appropriate box, type the name of the author.  This will be your name.  Do not include any punctuation in your name.

G. Click on "Create."

H. A screen with two windows will appear.  In the left window, you'll see the title and author of your story.  You'll be typing 
your source code in this window.  Your source code will describe your story in a way that Inform 7 can understand.  In the 
right window, for now, you'll see a list of chapters that are included in the documentation for Inform 7.

I. Near the top of your screen, you'll see two boxes with magnifying classes in them.  These are search boxes, one for 
searching through your source code and the other for searching through Inform's documentation.  Use the documentation 
search box to find answers to your questions about Inform. 

      II. Create your First Room

            A. In interactive fiction, a "room" can be any location, outdoors or indoors.

            B. Under the title and author, in the left window, leave a blank line, so that you can see
            where your story really begins.  Then type the name of your first room, followed by this phrase:

                  is a room.

            C.  In quotation marks, right after the sentence that names your room, type a good
           description for your room.  The quotation marks tell Inform to display text on the
          computer's screen, for the reader to see.  Your source code should now look something like this:

 

"A-221" by Brendan Desilets

 

A-221 is a room.  "A-221 is a fairly drab classroom, with twenty-four student desks and a like number of computers. It sports at least 
ten teacher-made signs about grammar and literature and one long, commercial poster.  A filing cabinet is the room's most 
prominent storage unit."

 

      III. Compile Your Story

            A. Compiling is changing your source code into a working interactive story.  If you
          have completed the steps outlined above, your story will now compile, though
          the player/character won't be able to do much.

            B. To compile your story, press the "Go" button at the top of your screen.  After a few
            seconds, if the story compiles correctly, you will see the description of your first room
          in the window on the right side of your screen.  If the story does not compile correctly,
            Inform 7 will try to tell you why it did not compile.

            C. If your story does not compile, Inform will use a little curved arrow to show where the mistake in your code seems to be.  
            Click on the arrow to see what you need to fix.

 

      IV. Create a Second Room

            A. Now, you can create a second room that connects to your first room.  Begin by naming your second room with a sentence like this one:

                  The Hallway is a room.

            B. Now, add a sentence that shows how the two room connect, such as:

                  It is east of A-221.

            C. In quotation marks, add the description of your new room.  The source code for
           your story should now look something like this:

 

"A-221" by Brendan Desilets

 

A-221 is a room.  "A-221 is a fairly drab classroom, with twenty-four student desks and a like number of computers. It sports at least 
ten teacher-made signs about grammar and literature and one long, commercial poster.  A filing cabinet is the room's most 
prominent storage unit."

 

The Hallway is a room.  It is east of A-221.  "This is an ordinary school hallway.  Room A-221 is to the west.  You can't think of any 
reason you would want to go in any other direction right now."

 

    V. Compile Your Story a Second Time

            A. Press the "Go" button to compile your story again.

            B. Once again, after a few seconds, if the story compiles successfully, you will     
          see the story running in the window on the right side of your screen.  If the story
            does not compile, Inform will try to tell you why it did not compile, so that you can
          fix the source code.

            C. Once your story with two rooms compiles, the player character will be able
          to move between the rooms.

 

    VI. Create Your First Object

            A. Actually, the rooms you have already created are objects of a sort.  Now, you'll create an object that can be picked up 
            and carried.

            B. After leaving a line space for easier reading, type the name of your object, followed by

                        is in A-221.

            C.  Then, if, for example, the object is a key, type:

            The description of the key is

            D. In quotation marks, type the description of your object.  The source code For your object should now look 
            something like this:

 

The key is in A-221. The description of the key is "An ordinary brass key."

 

            E. Compile your story once again.  The player character should now be able to pick up the object you created.

 

VII.  Create Your First Container

A. Inform makes it easy to create objects that can contain other objects.

B. Inform also makes it easy to create scenery.  The player-character cannot take a piece of scenery.

C. In this example, we will create a closed, locked container called the filing
cabinet.  Here is the source code for the filing cabinet:

The filing cabinet is scenery in A-221.  It is a closed openable container.  It is locked and lockable. "This filing cabinet is designed to store and organize all sorts of papers, but it could hold lots of other things, too."            

            D. In order to make the key unlock the filing cabinet, we add a sentence to the
          source code for the key.  This new sentence is:

                        The key unlocks the filing cabinet.

            E. Our source code for the key now looks like this:

 

The key is in A-221. The key unlocks the filing cabinet. The description of the key is "An ordinary brass key."

 

    VIII. Create Your First Rule

            A. A rule is a way of telling Inform about something that you want to happen,
            under certain conditions.  The statement of the conditions ends with a colon.

            B. Here is an example rule for our story.  This rule uses the word "say," which
          tells the computer to show some text to the player.  This rule applies only
          when the story begins.  Notice how this rule uses double quotation marks
            (the usual kind) and single quotation marks.

 

When play begins: say "Oh, no!  You've lost your red English binder.  But here comes your teacher.  Perhaps he's seen it.

 

'Maybe,' he says.  'I just locked  a binder in the filing cabinet in Room A-221.  See if it's yours.  You'll have to find the key  first, though.  
I'm not quite sure where I left it.'

 

You find your way to A-221 to begin the search."

 

     IX. Create Another Object, the Binder

            A. If the player-character is going to be able to find the missing binder, we must

            "implement" the binder.  In other words, we have to create it as an object.

            B. Here's some source code that creates the binder and places it inside the locked

            filing cabinet:

 

The binder is in the filing cabinet.  The description is "The red English binder that you lost recently.  You've been looking for it 
everywhere."

 

            C. Remember to compile your story frequently, to check for any problems.

 

     X. Create a Rule to End the Story

            A. Now, let's create a rule that ends the story in victory when the player-character
          gets the binder.  Every turn, this rule will check to see if the player-character has the binder.

            B. Here's the source code for this rule:

An every turn rule:
if the player is carrying the binder,
end the game in victory.

 

Here is the complete source code of our story so far:

_________________________________________________________________________

 

"A-221" by Brendan Desilets

 

When play begins: say "Oh, no!  You've lost your red English binder.  But here comes your teacher.  Perhaps he's seen it.

 

'Maybe,' he says.  'I just locked  a binder in the filing cabinet in Room A-221.  See if it's yours.  You'll have to find the key  
first, though.  I'm not quite sure where I left it.'

 

You find your way to A-221 to begin the search."

 

 

A-221 is a room.  "A-221 is a fairly drab classroom, with twenty-four student desks and a like number of computers. It sports 
at least ten teacher-made signs about grammar and literature and one long, commercial poster.  A filing cabinet is the 
room's most prominent storage unit."

 

The Hallway is a room.  It is east of A-221.  "This is an ordinary school hallway.  Room A-221 is to the west.  You can't think of 
any reason you would want to go in any other direction right now."

 

The key is in A-221. The key unlocks the filing cabinet. The description of the key is "An ordinary brass key."

 

The filing cabinet is scenery in A-221.  It is a closed openable container.  It is locked and lockable. "This filing cabinet is 
designed to store and organize all sorts of papers, but it could hold lots of other things, too."

 

The binder is in the filing cabinet.  The description is "The red English binder that you lost recently.  You've been looking for it 
everywhere."

 

An every turn rule:
if the player is carrying the binder,
end the game in victory.

 

 

It is now possible to read this story to its easy end.

 

XI.   Create Your First Character (Other Than the Player-Character)

A. Inform allows for the easy creation of characters.  A male character is called a man and a female character is called a woman, regardless of the character's age.

B. Here is the source code for a character:

Jeff is man in A-221.  The description of Jeff is "A sixth grader, wearing a baseball shirt.”

 

C.   Using brackets, we can add something special to Jeff’s description by creating a condition, or an

            "if," like this:

 

Jeff is a man in A-221.  The description of Jeff is "A sixth grader, wearing a baseball shirt.  [if the key is carried by Jeff] He is carrying a key." [end if]

 

XII.  Create Your First "Instead" Rule

A. The real creativity in writing interactive fiction happens when we change what
Inform ordinarily does.  For example, if the player-character attacks someone,
Inform usually responds, "Violence isn't the answer to this one."

B. If, instead, we want the player-character to lose if he or she attacks someone, we can make an "Instead" rule like this one:

Instead of attacking Jeff:
say "You have been suspended from school for violent behavior.";
end the game saying "And you have failed to recover your binder."

 

            C. Notice how we use the semicolon (;) to separate instructions we are giving to Inform.

 

XIII.Create More "Instead" Rules

A. "Instead" rules can be used for many purposes.  For example, we can use
them for conversation with characters.

B. To enable our character Jeff to talk about the key, we could use this code:

Instead of asking Jeff about "the key":
say "It's the key to the filing cabinet."

 

            C. In case the player wants to "ask Jeff about key," (leaving out the word "the")
          we can add this code:

 

Instead of asking Jeff about "key":
say "It's the key to the filing cabinet."

 

            D. We can use an "instead" rule to get Jeff to take the key if we offer it to him, using this code:

Instead of giving the key to Jeff:
say "Now Jeff has the key.";
move the key to Jeff.

 

            E. To get Jeff to give the key to the player, if asked, we could add:  

Instead of asking Jeff for the key:
say "Now you have the key.";
move the key to the player.

 

XIV.          Scoring

A.     You may have noticed that Inform seems to be trying to keep score in our sample story.

B.     Since scoring is probably not appropriate for our brief tale, let's add this to our source code:

Use no scoring.

 

XV.           Adding a Surprise

A.     Suppose that we want to add a surprise to the end of the game.  When the player takes the binder, he will find a 
homework pass under it.  The player will not see the pass until he or she takes the binder.

B.     First, let's implement the pass.  Notice that, for now, the pass will not be in any of the story's rooms.

 

The homework pass is a thing.  The description is "A special pass, signed by your teacher, that allows you to skip a 
homework assignment."  

C.    Now, we’ll make an "instead" rule to describe what happens when the player takes the binder

Instead of taking the binder:
say "As you take the binder, you find that, under it, is a homework pass, made out to you.";
move the pass to the cabinet;
move the binder to the player.

D.    Now, let's change our "every turn" rule, so that the game ends when the player takes the pass.

An every turn rule:
if the player is carrying the pass,
end the game in victory.

XVI.          Implementing

A.     There's lots more to implement, even in this very brief example.

B.     On your own, try implementing the posters and desks in Room-A221.

 

           

___________________________________________________________________

Here's the source code of our example story, so far.:

 

 

"A-221" by Brendan Desilets

  Use no scoring.

When play begins: say "Oh, no!  You've lost your red English binder.  But here comes your teacher.  Perhaps he's seen it.

'Maybe,' he says.  'I just locked  a binder in the filing cabinet in Room A-221.  See if it's yours.  You'll have to find the key  first, 
though.  I'm not quite sure where I left it.'

  You find your way to A-221 to begin the search."

 

A-221 is a room.  "A-221 is a fairly drab classroom, with twenty-four student desks and a like number of computers. It sports 
at least ten teacher-made signs about grammar and literature and one long, commercial poster.  A filing cabinet is the room's 
most prominent storage unit."

The Hallway is a room.  It is east of A-221.  "This is an ordinary school hallway.  Room A-221 is to the west.  You can't think 
of any reason you would want to go in any other direction right now."

The key is in A-221. The key unlocks the filing cabinet. The description of the key is "An ordinary brass key."

The filing cabinet is scenery in A-221.  It is a closed openable container.  It is locked and lockable. "This filing cabinet is 
designed to store and organize all sorts of papers, but it could hold lots of other things, too."

The binder is in the filing cabinet.  The description is "The red English binder that you lost recently.  You've been looking 
for it everywhere."

Jeff is man in A-221.  The description of Jeff is "A sixth grader, wearing a baseball shirt. [if the key is carried by Jeff] 
He is carrying a key.” [end if]

Instead of attacking Jeff:
say "You have been suspended from school for violent behavior.";
end the game saying "And you have failed to recover your binder."

Instead of asking Jeff about “the key”:
say “It's the key to the filing cabinet.”

Instead of asking Jeff about “key”:
say “It's the key to the filing cabinet.”

Instead of giving the key to Jeff:
say "Now Jeff has the key.";
move the key to Jeff.

Instead of asking Jeff for the key:
say "Now you have the key.";
move the key to the player.

The homework pass is a thing.  The description is "A special pass, signed by your teacher, that allows you to skip a homework 
assignment."

Instead of taking the binder:
say "As you take the binder, you find that, under it, is a homework pass, made out to you.";
move the pass to the cabinet;
move the binder to the player.

An every turn rule:
if the player is carrying the pass, 
end the game in victory.

.

 
XVII. Create Your First Value
	A. A value is a quality, or "property," that changes.  Actually we have already used values in our simple story.  
	For example, at the start of the story, our filing cabinet is closed and locked, but, later, it becomes unlocked and 
	open.  We didn't have to do anything special to set up these values because Inform already knew about closed 
	and locked containers.
	B. However, we can set up our own values or variables.  For instance, we can set up a value called "mood."  
	We can add that mood applies to people.  And we can set up as many moods as we want.  For now, let's 
	settle for "unhappy" and "pleased."  Let's set Jeff's opening mood as "unhappy."
	C. Here's the source code we should add:
Mood is a kind of value. The moods are unhappy and pleased. People have mood. The mood of Jeff is unhappy.
XVIII.  Use the "Mood" Value in Your Story
	A.  What can we do with values?  Actually, values are extremely powerful, and we can do a great deal with them.  
	Let's start by including Jeff's mood in his description, changing the description to read as follows:
Jeff is man in A-221. The description of Jeff is "A sixth grader, wearing a baseball shirt. [if the key is carried by Jeff] He is carrying 
a key [end if]. 
Jeff looks [the mood of Jeff]." 
        B. Now, let's invent a way to change Jeff's mood.  Suppose that we want the player to bribe Jeff in order to get the key 
	from him.  We can use this source code to create a coin that the player can use as a bribe:
The coin is a thing. The player carries the coin. The description of the coin is "A typical piece of currency-- worth something 
to most people."
	C. Now, let's create an instead rule that allows the player to change Jeff's mood by giving him the coin.  Here's the 
	source code:  
	
Instead of giving the coin to Jeff:
move the coin to Jeff;
now Jeff is pleased;
say "Jeff looks very pleased."
	D. Next, let's create an instead rule that forces the player to change Jeff's mood before the key can change hands.  
	The source code follows, but it's a little complicated:
Instead of asking Jeff for the key:
	if Jeff is unhappy:
		say "Jeff refuses to give the key, but points to the coin you're carrying.";
	if Jeff is pleased:
		say "Now you have the key.";
		move the key to the player.
	E. In the source code that appears above, indenting is important.  All of the important indents require that the writer 
	use the "Tab" key, not just a series of spaces.  Note that "Instead of asking Jeff for the key:" starts at the left margin.  
	Then we have two statements that are indented one tab.  These statements are "if Jeff is unhappy:" and "if Jeff is pleased:"  
	This indenting indicates that both of the "if" 
	statements are part of the instead rule that we are creating.
		1. Note that 
		say "Jeff refuses to give the key, but points to the coin you're carrying.";
		is indented under
		if Jeff is unhappy:

		This use of indenting shows that Jeff's refusal to give up the key happens only if Jeff is unhappy.
		2. Note, also, that
		say "Now you have the key.";
		and
		move the key to the player
		are indented under
		if Jeff is pleased:

		This use of indenting shows that both
		say "Now you have the key.";
		and
		move the key to the player
		happen if Jeff is pleased.
	F. This use of indenting to group statements together really helps in creating good stories with Inform 7.
________________________________________________________________
Here's the source code for our example story.
_________________________________________________________________

"A-221" by Brendan Desilets

  Use no scoring.

When play begins: say "Oh, no!  You've lost your red English binder.  But here comes your teacher.  Perhaps he's seen it.

'Maybe,' he says.  'I just locked  a binder in the filing cabinet in Room A-221.  See if it's yours.  You'll have to find the key  first, 
though.  I'm not quite sure where I left it.'

  You find your way to A-221 to begin the search."

 

A-221 is a room.  "A-221 is a fairly drab classroom, with twenty-four student desks and a like number of computers. It sports 
at least ten teacher-made signs about grammar and literature and one long, commercial poster.  A filing cabinet is the room's 
most prominent storage unit."

The Hallway is a room.  It is east of A-221.  "This is an ordinary school hallway.  Room A-221 is to the west.  You can't think 
of any reason you would want to go in any other direction right now."

The key is in A-221. The key unlocks the filing cabinet. The description of the key is "An ordinary brass key."

The filing cabinet is scenery in A-221.  It is a closed openable container.  It is locked and lockable. "This filing cabinet is 
designed to store and organize all sorts of papers, but it could hold lots of other things, too."

The binder is in the filing cabinet.  The description is "The red English binder that you lost recently.  You've been looking for it 
everywhere."  

The coin is a thing. The player carries the coin. The description of the coin is "A typical piece of currency-- worth something 
to most people."

Mood is a kind of value. The moods are unhappy and pleased. People have mood. The mood of Jeff is unhappy.

Jeff is man in A-221. The description of Jeff is "A sixth grader, wearing a baseball shirt. [if the key is carried by Jeff] 
He is carrying a key [end if]. Jeff looks [the mood of Jeff]."


Instead of attacking Jeff:
say "You have been suspended from school for violent behavior.";
end the game saying "And you have failed to recover your binder."

Instead of asking Jeff about “the key”:
say “It's the key to the filing cabinet.”

Instead of asking Jeff about “key”:
say “It's the key to the filing cabinet.”

Instead of giving the key to Jeff:
say "Now Jeff has the key.";
move the key to Jeff.

Instead of asking Jeff for the key:
    if Jeff is unhappy:
        say "Jeff refuses to give the key, but points to the coin you're carrying.";
    if Jeff is pleased:
        say "Now you have the key.";
        move the key to the player.

Instead of giving the coin to Jeff:
move the coin to Jeff;
now Jeff is pleased;
say "Jeff looks very pleased."

The homework pass is a thing.  The description is "A special pass, signed by your teacher, that allows you to skip a 
homework assignment."

Instead of taking the binder:
say "As you take the binder, you find that, under it, is a homework pass, made out to you.";
move the pass to the cabinet;
move the binder to the player.

An every turn rule:
if the player is carrying the pass, 
end the game in victory.

  

XIX. Creating Synonyms
	A. In any kind of writing, it's important for the writer to be considerate of the reader. Since interactive 
	fiction is an especially challenging form of writing and reading, it's especially important for
	the writer to think about the reader's needs.
	B. One way to help a reader is to make sure that he or she can use synonyms for the objects that we 
	implement.  Right now, as our story works, the reader can type "Give the coin to Jeff," and all will
	go well.  However, if the reader types, "Give the coin to the boy," the story fails to recognize the
	word "boy."
	C. To create a synonym for Jeff, we would add the following line to Jeff's description:

	Understand "boy" as Jeff. 
____________________________________________________________________________________
Here's the latest version of the story.  Notice that we've add a couple of synonyms for the binder.
____________________________________________________________________________________
"A-221" by Brendan Desilets 
Use no scoring.
When play begins: say "Oh, no! You've lost your red English binder. But here comes your teacher. Perhaps he's seen it.
'Maybe,' he says. 'I just locked a binder in the filing cabinet in Room A-221. See if it's yours. You'll have to find the key first, though. I'm not 
quite sure where I left it.'
You find your way to A-221 to begin the search."
A-221 is a room. "A-221 is a fairly drab classroom, with twenty-four student desks and a like number of computers. It sports at least ten 
teacher-made signs about grammar and literature and one long, commercial poster. A filing cabinet is the room's most prominent 
storage unit."
The Hallway is a room. It is east of A-221. "This is an ordinary school hallway. Room A-221 is to the west. You can't think of any 
reason you would want to go in any other direction right now."
The key is in A-221. The key unlocks the filing cabinet. The description of the key is "An ordinary brass key."
The filing cabinet is scenery in A-221. It is a closed openable container. It is locked and lockable. "This filing cabinet is designed to 
store and organize all sorts of papers, but it could hold lots of other things, too."
The binder is in the filing cabinet. The description is "The red English binder that you lost recently. You've been looking for it everywhere." 
Understand "notebook" as the binder. Understand "book" as the binder.
The coin is a thing. The player carries the coin. The description of the coin is "A typical piece of currency-- worth something to most people."
Mood is a kind of value. The moods are unhappy and pleased. People have mood. The mood of Jeff is unhappy.
Jeff is man in A-221. The description of Jeff is "A sixth grader, wearing a baseball shirt. [if the key is carried by Jeff] He is carrying 
a key [end if].  Jeff looks [the mood of Jeff]." Understand "boy" as Jeff.
Instead of attacking Jeff:
say "You have been suspended from school for violent behavior.";
end the game saying "And you have failed to recover your binder."
Instead of asking Jeff about “the key”:
say “It's the key to the filing cabinet.”
Instead of asking Jeff about “key”:
say “It's the key to the filing cabinet.”
Instead of giving the key to Jeff:
say "Now Jeff has the key.";
move the key to Jeff.
Instead of asking Jeff for the key:
    if Jeff is unhappy:
        say "Jeff refuses to give the key, but points to the coin you're carrying.";
    if Jeff is pleased:
        say "Now you have the key.";
        move the key to the player.
Instead of giving the coin to Jeff:
move the coin to Jeff;
now Jeff is pleased;
say "Jeff looks very pleased."
The homework pass is a thing. The description is "A special pass, signed by your teacher, that allows you to skip a homework assignment."
Instead of taking the binder:
say "As you take the binder, you find that, under it, is a homework pass, made out to you.";
move the pass to the cabinet;
move the binder to the player.
An every turn rule:
if the player is carrying the pass,
end the game in victory.

 

Send Email to Brendan Desilets