This repository has been archived by the owner on Dec 12, 2022. It is now read-only.
Home
You have arrived at version 2 of the Bali Type Compiler™ project. This project provides an API that can be used to compile the procedures defined in a type document into bytecode associated with each procedure such that the bytecode can be run on the Bali Virtual Machine™. The type compiler is built using the Bali Component Framework™.
Type documents are defined using Bali Document Notation™ to describe the attributes that make up documents of that type as well as the messages that that type of document can receive and process using the Bali Virtual Machine™.
Version 2 is the first stable version of the type compiler. There are likely be some bugs remaining in the code so watch for minor releases which fix bugs and add functionality, and for emergency bug patches. Minor releases (e.g. v2.x) and emergency bug patches (e.g. v2.x.y) should never break the public interface for the type compiler.
To whet your appetite, here is a short example of a compiled type document that implements the Tower of Hanoi game. The type compiler has compiled the procedures into assembly instructions that were then assembled into bytecode. The assembly instructions and bytecode are included in the compiled type definition. The type definition is also digitally notarized to prevent changes.
[
$parent: /nebula/abstractions/Component/v1
$description: "
This class encapsulates a /Tower of Hanoi/ game with three pegs (A, B, and C) and a
parameterized number of disks. To play the game do the following:
# Initialize a game with 3 disks.
`$game := [:]($type: /nebula/examples/TowerOfHanoi/v1)`
# Play the game.
`game.play()`
The output should be:
`
1. Move top disk on peg A to peg C
2. Move top disk on peg A to peg B
3. Move top disk on peg C to peg B
4. Move top disk on peg A to peg C
5. Move top disk on peg B to peg A
6. Move top disk on peg B to peg C
7. Move top disk on peg A to peg C
`
"($mediaType: "application/bsmd")
$attributes: [
$pegs: [
$description: "
The three pegs (A, B and C) that are used to hold the disks.
"($mediaType: "application/bsmd")
$type: /nebula/collections/Catalog/v1(
$keyType: /nebula/strings/Symbol/v1
$valueType: /nebula/collections/Stack/v1($itemType: /nebula/elements/Number/v1($range: [1..]))
)
]($type: /nebula/aspects/Attribute/v1)
$steps: [
$description: "
The steps needed to move the disks.
"($mediaType: "application/bsmd")
$type: /nebula/collections/List/v1($itemType: /nebula/strings/Text/v1)
]($type: /nebula/aspects/Attribute/v1)
]($type: /nebula/collections/Catalog/v1($valueType: /nebula/aspects/Attribute/v1))
$operations: [
$play: [
$description: "
This procedure causes the game to (re)initialize itself and play the game.
"($mediaType: "application/bsmd")
$parameters: [
$numberOfDisks: [
$description: "
The number of disks.
"($mediaType: "application/bsmd")
$type: /nebula/elements/Number/v1($range: [1..])
]($type: /nebula/aspects/Parameter/v1)
]($type: /nebula/collections/Catalog/v1($valueType: /nebula/aspects/Parameter/v1))
$type: /nebula/collections/Catalog/v1(
$keyType: /nebula/elements/Number/v1($range: [1..])
$valueType: /nebula/strings/Text/v1
)
]($type: /nebula/aspects/Operation/v1)
$moveTower: [
$description: "
This procedure causes the game to move a tower of disks of a certain height
from one peg to another peg using a third peg as a buffer.
"($mediaType: "application/bsmd")
$parameters: [
$height: [
$description: "
The height of the tower to be moved.
"($mediaType: "application/bsmd")
$type: /nebula/elements/Number/v1($range: [1..])
]($type: /nebula/aspects/Parameter/v1)
$fromPeg: [
$description: "
The peg from which the disks originate.
"($mediaType: "application/bsmd")
$type: /nebula/strings/Text/v1
]($type: /nebula/aspects/Parameter/v1)
$toPeg: [
$description: "
The peg to which the disks should be moved.
"($mediaType: "application/bsmd")
$type: /nebula/strings/Text/v1
]($type: /nebula/aspects/Parameter/v1)
$withPeg: [
$description: "
The peg to use to buffer the disks during the move.
"($mediaType: "application/bsmd")
$type: /nebula/strings/Text/v1
]($type: /nebula/aspects/Parameter/v1)
]($type: /nebula/collections/Catalog/v1($valueType: /nebula/aspects/Parameter/v1))
](
$type: /nebula/aspects/Operation/v1
$access: $private
)
$moveDisk: [
$description: "
This procedure causes the game to move the top disk from one peg to another.
"($mediaType: "application/bsmd")
$parameters: [
$fromPeg: [
$description: "
The peg from which the disk originates.
"($mediaType: "application/bsmd")
$type: /nebula/strings/Text/v1
]($type: /nebula/aspects/Parameter/v1)
$toPeg: [
$description: "
The peg to which the disk should be moved.
"($mediaType: "application/bsmd")
$type: /nebula/strings/Text/v1
]($type: /nebula/aspects/Parameter/v1)
]($type: /nebula/collections/Catalog/v1($valueType: /nebula/aspects/Parameter/v1))
](
$type: /nebula/aspects/Operation/v1
$access: $private
)
]($type: /nebula/collections/Catalog/v1($valueType: /nebula/aspects/Operation/v1))
$methods: [
$play: [
$description: "
This method implements the `$play` operation defined in this type.
"($mediaType: "application/bsmd")
$procedure: {
target[$pegs] := [
"peg A": [ ]($type: /nebula/collections/Stack/v1($itemType: /nebula/elements/Number/v1($range: [1..])))
"peg B": [ ]($type: /nebula/collections/Stack/v1($itemType: /nebula/elements/Number/v1($range: [1..])))
"peg C": [ ]($type: /nebula/collections/Stack/v1($itemType: /nebula/elements/Number/v1($range: [1..])))
]
target[$steps] := [ ]
$disks := range(numberOfDisks, 1)
with each $n in disks do {
target[$pegs, "peg A"].addItem(n)
}
target.moveTower(numberOfDisks, "peg A", "peg C", "peg B")
return target[$steps].asCatalog()
}
$instructions: "
1.EvaluateStatement:
NOTE --Place the recipient and the index of its attribute on the stack.
PUSH ARGUMENT $target
PUSH LITERAL `$pegs`
NOTE --Place an empty catalog on the stack.
CALL $catalog
NOTE --Add an item to the catalog.
PUSH LITERAL `"peg A"`
NOTE --Place an empty stack on the stack.
NOTE --Place a catalog of the parameters on the stack.
CALL $catalog
PUSH LITERAL `$type`
PUSH LITERAL `/nebula/collections/Stack/v1`
NOTE --Place a catalog of the parameters on the stack.
CALL $catalog
PUSH LITERAL `$itemType`
PUSH LITERAL `/nebula/elements/Number/v1`
NOTE --Place a catalog of the parameters on the stack.
CALL $catalog
PUSH LITERAL `$range`
NOTE --Place a range on the stack.
PUSH LITERAL `".."`
CALL $range WITH 1 ARGUMENT
NOTE --Set the first item in the range.
PUSH LITERAL `1`
CALL $setFirst WITH 2 ARGUMENTS
CALL $setAttribute WITH 3 ARGUMENTS
CALL $setAttribute WITH 3 ARGUMENTS
CALL $setAttribute WITH 3 ARGUMENTS
CALL $stack WITH 1 ARGUMENT
CALL $association WITH 2 ARGUMENTS
CALL $addItem WITH 2 ARGUMENTS
NOTE --Add another item to the catalog.
PUSH LITERAL `"peg B"`
NOTE --Place an empty stack on the stack.
NOTE --Place a catalog of the parameters on the stack.
CALL $catalog
PUSH LITERAL `$type`
PUSH LITERAL `/nebula/collections/Stack/v1`
NOTE --Place a catalog of the parameters on the stack.
CALL $catalog
PUSH LITERAL `$itemType`
PUSH LITERAL `/nebula/elements/Number/v1`
NOTE --Place a catalog of the parameters on the stack.
CALL $catalog
PUSH LITERAL `$range`
NOTE --Place a range on the stack.
PUSH LITERAL `".."`
CALL $range WITH 1 ARGUMENT
NOTE --Set the first item in the range.
PUSH LITERAL `1`
CALL $setFirst WITH 2 ARGUMENTS
CALL $setAttribute WITH 3 ARGUMENTS
CALL $setAttribute WITH 3 ARGUMENTS
CALL $setAttribute WITH 3 ARGUMENTS
CALL $stack WITH 1 ARGUMENT
CALL $association WITH 2 ARGUMENTS
CALL $addItem WITH 2 ARGUMENTS
NOTE --Add another item to the catalog.
PUSH LITERAL `"peg C"`
NOTE --Place an empty stack on the stack.
NOTE --Place a catalog of the parameters on the stack.
CALL $catalog
PUSH LITERAL `$type`
PUSH LITERAL `/nebula/collections/Stack/v1`
NOTE --Place a catalog of the parameters on the stack.
CALL $catalog
PUSH LITERAL `$itemType`
PUSH LITERAL `/nebula/elements/Number/v1`
NOTE --Place a catalog of the parameters on the stack.
CALL $catalog
PUSH LITERAL `$range`
NOTE --Place a range on the stack.
PUSH LITERAL `".."`
CALL $range WITH 1 ARGUMENT
NOTE --Set the first item in the range.
PUSH LITERAL `1`
CALL $setFirst WITH 2 ARGUMENTS
CALL $setAttribute WITH 3 ARGUMENTS
CALL $setAttribute WITH 3 ARGUMENTS
CALL $setAttribute WITH 3 ARGUMENTS
CALL $stack WITH 1 ARGUMENT
CALL $association WITH 2 ARGUMENTS
CALL $addItem WITH 2 ARGUMENTS
NOTE --Assign the result as the value of the attribute.
CALL $setAttribute WITH 3 ARGUMENTS
PULL COMPONENT
2.EvaluateStatement:
NOTE --Place the recipient and the index of its attribute on the stack.
PUSH ARGUMENT $target
PUSH LITERAL `$steps`
NOTE --Place an empty list on the stack.
CALL $list
NOTE --Assign the result as the value of the attribute.
CALL $setAttribute WITH 3 ARGUMENTS
PULL COMPONENT
3.EvaluateStatement:
PUSH ARGUMENT $numberOfDisks
PUSH LITERAL `1`
CALL $range WITH 2 ARGUMENTS
SAVE VARIABLE $disks
4.WithStatement:
LOAD VARIABLE $disks
SEND $iterator TO COMPONENT
SAVE VARIABLE $iterator-2
4.1.ConditionClause:
LOAD VARIABLE $iterator-2
SEND $hasNext TO COMPONENT
JUMP TO 4.WithStatementDone ON FALSE
LOAD VARIABLE $iterator-2
SEND $next TO COMPONENT
SAVE VARIABLE $n
4.1.1.EvaluateStatement:
PUSH ARGUMENT $target
PUSH LITERAL `$pegs`
CALL $attribute WITH 2 ARGUMENTS
PUSH LITERAL `"peg A"`
CALL $attribute WITH 2 ARGUMENTS
NOTE --Place a list of the message arguments on the stack.
CALL $list
LOAD VARIABLE $n
CALL $addItem WITH 2 ARGUMENTS
NOTE --Send the message with its arguments to the recipient.
SEND $addItem TO COMPONENT WITH ARGUMENTS
SAVE VARIABLE $result-1
4.ConditionRepeat:
JUMP TO 4.1.ConditionClause
4.WithStatementDone:
JUMP TO NEXT INSTRUCTION
5.EvaluateStatement:
PUSH ARGUMENT $target
NOTE --Place a list of the message arguments on the stack.
CALL $list
PUSH ARGUMENT $numberOfDisks
CALL $addItem WITH 2 ARGUMENTS
PUSH LITERAL `"peg A"`
CALL $addItem WITH 2 ARGUMENTS
PUSH LITERAL `"peg C"`
CALL $addItem WITH 2 ARGUMENTS
PUSH LITERAL `"peg B"`
CALL $addItem WITH 2 ARGUMENTS
NOTE --Send the message with its arguments to the recipient.
SEND $moveTower TO COMPONENT WITH ARGUMENTS
SAVE VARIABLE $result-1
6.ReturnStatement:
PUSH ARGUMENT $target
PUSH LITERAL `$steps`
CALL $attribute WITH 2 ARGUMENTS
SEND $asCatalog TO COMPONENT
PULL RESULT
"($mediaType: "application/basm")
$bytecode: '
38012805C012280BC01228082802C01228042803C01228062809C8622801
D075D874D874D874C880D009D001280CC01228082802C01228042803C012
28062809C8622801D075D874D874D874C880D009D001280DC01228082802
C01228042803C01228062809C8622801D075D874D874D874C880D009D001
D874480038012807C047D874480038022801D06280016001E00480026002
E003185C6002E006800338012805D00A280BD00AC0476003D001E8018004
004B00003801C0473802D001280BD001280DD001280CD001E80580043801
2807D00AE0025000
'(
$encoding: $base16
$mediaType: "application/bcod"
)
$arguments: [
$target: none
$numberOfDisks: none
]
$variables: [
$disks
$iterator-2
$n
$result-1
]($type: /nebula/collections/Set/v1($itemType: /nebula/strings/Symbol/v1))
$messages: [
$addItem
$asCatalog
$hasNext
$iterator
$moveTower
$next
]($type: /nebula/collections/Set/v1($itemType: /nebula/strings/Symbol/v1))
$addresses: [
"1.EvaluateStatement": 1
"2.EvaluateStatement": 63
"3.EvaluateStatement": 68
"4.WithStatement": 72
"4.1.ConditionClause": 75
"4.1.1.EvaluateStatement": 81
"4.ConditionRepeat": 91
"4.WithStatementDone": 92
"5.EvaluateStatement": 93
"6.ReturnStatement": 105
]($type: /nebula/collections/Catalog/v1($keyType: /nebula/strings/Text/v1, $valueType: /nebula/interfaces/Discrete/v1))
]($type: /nebula/aspects/Method/v1)
$moveTower: [
$description: "
This method implements the `$moveTower` operation defined in this type.
"($mediaType: "application/bsmd")
$procedure: {
if height then {
target.moveTower(height - 1, fromPeg, withPeg, toPeg)
target.moveDisk(fromPeg, toPeg)
target.moveTower(height - 1, withPeg, toPeg, fromPeg)
}
}
$instructions: "
1.IfStatement:
JUMP TO NEXT INSTRUCTION
1.1.ConditionClause:
PUSH ARGUMENT $height
JUMP TO 1.IfStatementDone ON FALSE
1.1.1.EvaluateStatement:
PUSH ARGUMENT $target
NOTE --Place a list of the message arguments on the stack.
CALL $list
PUSH ARGUMENT $height
PUSH LITERAL `1`
CALL $difference WITH 2 ARGUMENTS
CALL $addItem WITH 2 ARGUMENTS
PUSH ARGUMENT $fromPeg
CALL $addItem WITH 2 ARGUMENTS
PUSH ARGUMENT $withPeg
CALL $addItem WITH 2 ARGUMENTS
PUSH ARGUMENT $toPeg
CALL $addItem WITH 2 ARGUMENTS
NOTE --Send the message with its arguments to the recipient.
SEND $moveTower TO COMPONENT WITH ARGUMENTS
SAVE VARIABLE $result-1
1.1.2.EvaluateStatement:
PUSH ARGUMENT $target
NOTE --Place a list of the message arguments on the stack.
CALL $list
PUSH ARGUMENT $fromPeg
CALL $addItem WITH 2 ARGUMENTS
PUSH ARGUMENT $toPeg
CALL $addItem WITH 2 ARGUMENTS
NOTE --Send the message with its arguments to the recipient.
SEND $moveDisk TO COMPONENT WITH ARGUMENTS
SAVE VARIABLE $result-1
1.1.3.EvaluateStatement:
PUSH ARGUMENT $target
NOTE --Place a list of the message arguments on the stack.
CALL $list
PUSH ARGUMENT $height
PUSH LITERAL `1`
CALL $difference WITH 2 ARGUMENTS
CALL $addItem WITH 2 ARGUMENTS
PUSH ARGUMENT $withPeg
CALL $addItem WITH 2 ARGUMENTS
PUSH ARGUMENT $toPeg
CALL $addItem WITH 2 ARGUMENTS
PUSH ARGUMENT $fromPeg
CALL $addItem WITH 2 ARGUMENTS
NOTE --Send the message with its arguments to the recipient.
SEND $moveTower TO COMPONENT WITH ARGUMENTS
SAVE VARIABLE $result-1
1.IfStatementDone:
LOAD VARIABLE $result-1
PULL RESULT
"($mediaType: "application/basm")
$bytecode: '
0000380218283801C04738022801D021D0013803D0013805D0013804D001
E80280013801C0473803D0013804D001E80180013801C04738022801D021
D0013805D0013804D0013803D001E802800160015000
'(
$encoding: $base16
$mediaType: "application/bcod"
)
$arguments: [
$target: none
$height: none
$fromPeg: none
$toPeg: none
$withPeg: none
]
$variables: [
$result-1
]($type: /nebula/collections/Set/v1($itemType: /nebula/strings/Symbol/v1))
$messages: [
$moveDisk
$moveTower
]($type: /nebula/collections/Set/v1($itemType: /nebula/strings/Symbol/v1))
$addresses: [
"1.IfStatement": 1
"1.1.ConditionClause": 2
"1.1.1.EvaluateStatement": 4
"1.1.2.EvaluateStatement": 18
"1.1.3.EvaluateStatement": 26
"1.IfStatementDone": 40
]($type: /nebula/collections/Catalog/v1($keyType: /nebula/strings/Text/v1, $valueType: /nebula/interfaces/Discrete/v1))
]($type: /nebula/aspects/Method/v1)
$moveDisk: [
$description: "
This method implements the `$moveDisk` operation defined in this type.
"($mediaType: "application/bsmd")
$procedure: {
$disk := target[$pegs, fromPeg].removeItem()
target[$pegs, toPeg].addItem(disk)
target[$steps].append("Move disk {disk} from {fromPeg} to {toPeg}.")
}
$instructions: "
1.EvaluateStatement:
PUSH ARGUMENT $target
PUSH LITERAL `$pegs`
CALL $attribute WITH 2 ARGUMENTS
PUSH ARGUMENT $fromPeg
CALL $attribute WITH 2 ARGUMENTS
SEND $removeItem TO COMPONENT
SAVE VARIABLE $disk
2.EvaluateStatement:
PUSH ARGUMENT $target
PUSH LITERAL `$pegs`
CALL $attribute WITH 2 ARGUMENTS
PUSH ARGUMENT $toPeg
CALL $attribute WITH 2 ARGUMENTS
NOTE --Place a list of the message arguments on the stack.
CALL $list
LOAD VARIABLE $disk
CALL $addItem WITH 2 ARGUMENTS
NOTE --Send the message with its arguments to the recipient.
SEND $addItem TO COMPONENT WITH ARGUMENTS
SAVE VARIABLE $result-1
3.EvaluateStatement:
PUSH ARGUMENT $target
PUSH LITERAL `$steps`
CALL $attribute WITH 2 ARGUMENTS
NOTE --Place a list of the message arguments on the stack.
CALL $list
PUSH LITERAL `"Move disk {disk} from {fromPeg} to {toPeg}."`
CALL $addItem WITH 2 ARGUMENTS
NOTE --Send the message with its arguments to the recipient.
SEND $append TO COMPONENT WITH ARGUMENTS
SAVE VARIABLE $result-1
LOAD VARIABLE $result-1
PULL RESULT
"($mediaType: "application/basm")
$bytecode: '
38012805D00A3802D00AE003800138012805D00A3803D00AC0476001D001
E801800238012807D00AC047280AD001E802800260025000
'(
$encoding: $base16
$mediaType: "application/bcod"
)
$arguments: [
$target: none
$fromPeg: none
$toPeg: none
]
$variables: [
$disk
$result-1
]($type: /nebula/collections/Set/v1($itemType: /nebula/strings/Symbol/v1))
$messages: [
$addItem
$append
$removeItem
]($type: /nebula/collections/Set/v1($itemType: /nebula/strings/Symbol/v1))
$addresses: [
"1.EvaluateStatement": 1
"2.EvaluateStatement": 8
"3.EvaluateStatement": 18
]($type: /nebula/collections/Catalog/v1($keyType: /nebula/strings/Text/v1, $valueType: /nebula/interfaces/Discrete/v1))
]($type: /nebula/aspects/Method/v1)
]($type: /nebula/collections/Catalog/v1($valueType: /nebula/aspects/Method/v1))
$literals: [
1
/nebula/collections/Stack/v1
/nebula/elements/Number/v1
$itemType
$pegs
$range
$steps
$type
".."
"Move disk {disk} from {fromPeg} to {toPeg}."
"peg A"
"peg B"
"peg C"
]($type: /nebula/collections/Set/v1)
](
$type: /nebula/types/Class/v1
$tag: #1M9WB8VXAWP8A0T1K3MHWD4ZFBM3MG7T
$version: v1
$permissions: /nebula/permissions/public/v1
$previous: none
)
The Bali Type Compiler™ generates bytecode for compiled procedures that can be run on the Bali Virtual Machine™.
To dive in deeper on the parts of the type compiler that interest you most, click on links listed in
the side bar in the upper right corner