Functions

and

Performs a boolean and operation.

and(expr1, expr2)

See also

• not
• or

clearBuffer

Clear any un-flushed messages.

do:
  - print("one")
  - print("two")
  - clearBuffer()
  - print("three")

Output

three

close

Close something. Errors if the item is not openable.

close(item)

see also

• isOpenable
• open

closeExit

Closes an existing exit between two rooms, blocking the player from navigating between them.

closeExit(room, direction)

closeExit(northRoom, 'south')

item: door
tags:
  - cloasable
exits: 
  south: southRom
before:
  close(this): closeExit(thisRoom, 'south')

see all

• openExit

delTag

Deletes a tag on an entity

delTag(entity, tag-name)

room: northRoom
name: north room
tags:
  - start
  - foo
afterTurn():
  - print(hasTag(northRoom, 'foo'))
  - delTag(northRoom, 'foo')
  - print(hasTag(northRoom, 'foo'))

$ wait
> true
false

See also

• hasTag
• setTag

error

Print an error message. Indicates something has gone wrong with the execution of the game.

print("Something has gone wrong")

see also

• print
• say
• warn

format

Format a string. Strings can be specified using mustache expressions. format can be used to evaluate these strings.

Implicit formatting

Strings containing mustache expressions are usually implicitly evaluated, and you don't normally need to call format. Only needs to be used if you want to explicitly control what data is passed into the expression.

To avoid implicit evaluation format strings should be defined under a templates property, or inlined into the expression.

room: northRoom
name: north room
templates:
  formatStr: "foo = {{foo}}, qux = {{qux}}"
afterTurn():
  - foo = 'bar'
  - qux = 'baz'
  - print(format(templates.formatStr))

$ wait
> foo = bar, qux = baz

gameOver

Triggers the game over state, and displays the provided message

gameOver(message)

getEntity

Returns the entity with the corresponding is.

getEntity(entityId);

do:
  - mouse = getEntity('mouse1')
  - mouse.in_trap = true

getFullName

Return the name of an entity, including it's article (ie a, or the).

If no article is specifies the is assumed.

---
item: mouse1
name: brown mouse
verbs:
  - examine
before:
  examine(this): print("You see " + getFullName(this) + ".")
---
item: mouse2
name: white mouse
article: 'a'
verbs:
  - examine
before:
  examine(this): print("You see " + getFullName(this) + ".")
---

$ examine brown mouse
> You see the brown mouse.

$ examine white mouse
> You see a white mouse.

see also

• getName

getInventory

Returns all the items the player is carrying

getInventory()

see also

• itemsAtLocation

getLocation

Return the id of the players current location

getLocation()

see also

• isAtLocation

getName

Return the name of an entity, or it's id if it doesn't have a name.

item: mouse1
name: brown mouse
verbs:
  - examine
before:
  examine(this): print("You see " + getName(this))

$ examine brown mouse
> You see brown mouse

see also

• getFullName

getMetadata

Returns a metadata object. These are usually properties of the game object.

getMetadata(key)

do:
  - print('name = ' + getMetadata('name'))
  - print('author = ' + getMetadata('author'))

getPlayer

Returns the player object.

do:
  - player = getPlayer()
  - print(player.score)

getProperty

Return a game property. These are usually defined in properties.yaml, but you can also define your own.

getProperty(propertyKey, defaultValue)

---
property: specialStrings
messages:
  hello: "Hello World"
  goodbye: "Goodbye World"
---
rule: everyTurn
afterTurn(): 
  - print(getProperty('specialStrings.messages.hello', "Hi there"))
  - print(getProperty('specialStrings.messages.howAreYou', 'Howdy'))
---

> Hello World
> Howdy

getScore

Returns the players current score

getScore()

see also

• score

hasTag

Checks if a tag is set on an entity.

hasTag(entity, tag-name)

room: northRoom
name: north room
tags:
  - start
  - foo
afterTurn():
  - print(hasTag(northRoom, 'foo'))
  - print(hasTag(northRoom, 'bar'))

$ wait
> true
false

See also

• setTag
• delTag

hide

Sets the hidden tag on an item, hiding it from the player. Does the reverse of reveal

hide(item)

see also

• reveal

isAtLocation

Checks if an item is at a particular location

isAtLocation(item, room)

when: isAtLocation(mouse, northRoom)
then: print("squeek!")

see also

• getLocation

isCarrying

Returns true if the item is carried by the player

isCarrying(item)

see also

• isHolding

isHolding

Returns true if the item is held by the player

isHolding(item)

see also

• isCarrying

isInContainer

Return true if an item is in a container.

---
item: purse
tags:
  - container
---
item: coin
location: purse
before:
  drop(this): 
    - when: isInContainer(this)
      then: print("You can't drop the coin whilst it is inside the purse")
      otherwise:
        - return(false)
---

isOpenable

Returns true if the item is something that can be opened. The open/closed status has no effect on this call

isOpenable(item)

see also

• open
• close

itemsAtLocation

Returns an array containing all the entities at the specified location

itemsAtLocation(room)

see also

• isAtLocation
• getInventory

move

Move an item to another location

move(item).to(location)

move(cat).to(kitchen)

not

Performs a boolean not operation.

not(expression)

See also

• and
• or

obj

Create an object.

do: 
  - myObj = obj()
  - myObj.property1 = "Hello"
  - myObj.property2 = 4

open

Open something. Errors if the item is not openable.

open(item)

see also

• isOpenable
• close

openExit

Opens a new exit from a room. Once enabled the appropriate navigation option will be available to the player.

openExit(room, direction, destination)

openExit(northRoom, 'south', southRoom)

item: door
tags:
  - openable
before:
  open(this): openExit(thisRoom, 'south', southRoom)

see also

• closeExit

or

Performs a boolean or operation.

or(expr1, expr2)

See also

• not
• and

print

Prints a message.

print("Hello World!")

see also

• say
• warn
• error

random

Returns a random number between a two values (inclusive)

random(low, high)

do: 
  - print(random(1, 6))
  - print(random(1, 6))
  - print(random(1, 6))
  - print(random(1, 6))

Output

3
6
1
4

return

Returns the value of the expression. Can't be used to return early from a function. Used to label the final value in a series of expressions.

return(expr)

reveal

Removes the hidden tag on an item. Makes it visible to the player

---
item: diamond
location: rubbish
tags:
  - carryable
  - hidden
---
item: rubbish
description: A pile of stinking rubbish
location: northRoom
after:
  examine(this):
    when: hasTag(diamond,'hidden')
    then: reveal(diamond)
---

see also

• hide

say

Prints out a message surrounded by quotes.

say(message)

say("Hello World")

Outputs:

"Hello World"

see also

• print
• warn
• error

score

Increase the players score by the specified number of points. Consider using a once rule to avoid it repeatedly triggering.

score(points)

item: ball
name: ball
description: you'll score a point if you pick the ball up!
tags:
  - carryable
after:
  get(this):
    once: score(1)

see also

• getScore

setLocation

Sets the location of the player.

setLocation(newLocation)

setLocation(northRoom)

setTag

Sets a tag on an entity

setTag(entity, tag-name)

room: northRoom
name: north room
tags:
  - start
  - foo
afterTurn():
  - print(hasTag(northRoom, 'bar'))
  - setTag(northRoom, 'bar')
  - print(hasTag(northRoom, 'bar'))

$ wait
> false
true

See also

• hasTag
• delTag

tick

Force time to pass. Some verbs are classified as instant (such as look, and examine), and don't force a new turn. tick can override this.

item: longScroll
name: long scroll
desc: The scroll is *really* long, and time passes as you read it.
after:
  examine(this): tick()

warn

Print a warning message. Indicates that something may have gone wrong with the execution of the game, but the game can still continue.

print("Something does not seem right")

• print
• say
• error