amber/st/parser.st

Object subclass: #PPParser
	instanceVariableNames: 'memo'
	category: 'Parser'!


!PPParser methodsFor: 'accessing'!

memo
	^memo
! !

!PPParser methodsFor: 'error handling'!

onFailure: aBlock
	^PPFailureActionParser on: self block: aBlock
! !

!PPParser methodsFor: 'initialization'!

initialize
	memo := Dictionary new
! !

!PPParser methodsFor: 'operations'!

, aParser
	^PPSequenceParser with: self with: aParser
!

/ aParser
	^PPChoiceParser with: self with: aParser
!

==> aBlock
	^PPActionParser on: self block: aBlock
!

flatten
	^PPFlattenParser on: self
!

memoizedParse: aStream
	| start end node |
	start := aStream position.
	^self memo at: start 
	    ifPresent: [:value |
		aStream position: (self memo at: start) second.
		value first]
	    ifAbsent: [
		node := self parse: aStream.
		end := aStream position.
		self memo at: start put: (Array with: node with: end).
		node]
!

not
	^PPNotParser on: self
!

optional
	^self / PPEpsilonParser new
!

plus
	^PPRepeatingParser on: self min: 1
!

star
	^PPRepeatingParser on: self min: 0
!

withSource
	^PPSourceParser on: self
! !

!PPParser methodsFor: 'parsing'!

parse: aStream
	self subclassResponsibility
!

parseAll: aStream
	| result |
	result := (PPSequenceParser with: self with: PPEOFParser new) memoizedParse: aStream.
	^result isParseFailure 
	    ifTrue: [self error: (result messageFor: aStream contents)]
	    ifFalse: [result first]
! !


PPParser subclass: #PPEOFParser
	instanceVariableNames: ''
	category: 'Parser'!


!PPEOFParser methodsFor: 'parsing'!

parse: aStream
	^aStream atEnd 
	    ifFalse: [
		PPFailure new reason: 'EOF expected' at: aStream position]
	    ifTrue: [nil]
! !


PPParser subclass: #PPAnyParser
	instanceVariableNames: ''
	category: 'Parser'!


!PPAnyParser methodsFor: 'parsing'!

parse: aStream
	^aStream atEnd
	    ifTrue: [PPFailure new
			 reason: 'did not expect EOF' at: aStream position]
	    ifFalse: [aStream next]
! !


PPParser subclass: #PPEpsilonParser
	instanceVariableNames: ''
	category: 'Parser'!


!PPEpsilonParser methodsFor: 'parsing'!

parse: aStream
	^nil
! !


PPParser subclass: #PPStringParser
	instanceVariableNames: 'string'
	category: 'Parser'!


!PPStringParser methodsFor: 'accessing'!

string
	^string
!

string: aString
	string := aString
! !

!PPStringParser methodsFor: 'parsing'!

parse: aStream
	| position result |
	position := aStream position.
	result := aStream next: self string size.
	^result = self string
	    ifTrue: [result]
	    ifFalse: [
		aStream position: position.
		PPFailure new reason: 'Expected ', self string, ' but got ', (result at: position) printString; yourself]
! !


PPParser subclass: #PPCharacterParser
	instanceVariableNames: 'regexp'
	category: 'Parser'!


!PPCharacterParser methodsFor: 'accessing'!

string: aString
	regexp := RegularExpression fromString: '[', aString, ']'
! !

!PPCharacterParser methodsFor: 'parsing'!

parse: aStream
	^(aStream peek notNil and: [self match: aStream peek])
	    ifTrue: [aStream next]
	    ifFalse: [PPFailure new reason: 'Could not match' at: aStream position]
! !

!PPCharacterParser methodsFor: 'private'!

match: aString
	^aString match: regexp
! !


PPParser subclass: #PPListParser
	instanceVariableNames: 'parsers'
	category: 'Parser'!


!PPListParser class methodsFor: 'instance creation'!

with: aParser with: anotherParser
	    ^self withAll: (Array with: aParser with: anotherParser)
!

withAll: aCollection
	    ^self new
		parsers: aCollection;
		yourself
! !

!PPListParser methodsFor: 'accessing'!

parsers
	^parsers ifNil: [#()]
!

parsers: aCollection
	parsers := aCollection
! !

!PPListParser methodsFor: 'copying'!

copyWith: aParser
	^self class withAll: (self parsers copyWith: aParser)
! !


PPListParser subclass: #PPSequenceParser
	instanceVariableNames: ''
	category: 'Parser'!


!PPSequenceParser methodsFor: 'copying'!

, aRule
	^self copyWith: aRule
! !

!PPSequenceParser methodsFor: 'parsing'!

parse: aStream
	| start elements element |
	start := aStream position.
	elements := #().
	self parsers 
	    detect: [:each |
		element := each memoizedParse: aStream.
		elements add: element.
		element isParseFailure] 
	    ifNone: [].
	^element isParseFailure
	    ifFalse: [elements]
	    ifTrue: [aStream position: start. element]
! !


PPListParser subclass: #PPChoiceParser
	instanceVariableNames: ''
	category: 'Parser'!


!PPChoiceParser methodsFor: 'copying'!

/ aRule
	^self copyWith: aRule
! !

!PPChoiceParser methodsFor: 'parsing'!

parse: aStream
	| result |
	self parsers
    	    detect: [:each |
		result := each memoizedParse: aStream.
		result isParseFailure not]
	    ifNone: [].
	^result
! !


PPParser subclass: #PPDelegateParser
	instanceVariableNames: 'parser'
	category: 'Parser'!


!PPDelegateParser class methodsFor: 'instance creation'!

on: aParser
	    ^self new
		parser: aParser;
		yourself
! !

!PPDelegateParser methodsFor: 'accessing'!

parser
	^parser
!

parser: aParser
	parser := aParser
! !

!PPDelegateParser methodsFor: 'parsing'!

parse: aStream
	^self parser memoizedParse: aStream
! !


PPDelegateParser subclass: #PPAndParser
	instanceVariableNames: ''
	category: 'Parser'!


!PPAndParser methodsFor: 'parsing'!

basicParse: aStream
	| element position |
	position := aStream position.
	element := self parser memoizedParse: aStream.
	aStream position: position.
	^element
!

parse: aStream
	^self basicParse: aStream
! !


PPAndParser subclass: #PPNotParser
	instanceVariableNames: ''
	category: 'Parser'!


!PPNotParser methodsFor: 'parsing'!

parse: aStream
	| element |
	element := self basicParse: aStream.
	^element isParseFailure 
	    ifTrue: [nil]
	    ifFalse: [PPFailure reason: element at: aStream position]
! !


PPDelegateParser subclass: #PPActionParser
	instanceVariableNames: 'block'
	category: 'Parser'!


!PPActionParser class methodsFor: 'instance creation'!

on: aParser block: aBlock
	    ^self new
		parser: aParser;
		block: aBlock;
		yourself
! !

!PPActionParser methodsFor: 'accessing'!

block
	^block
!

block: aBlock
	block := aBlock
! !

!PPActionParser methodsFor: 'parsing'!

parse: aStream
	| element |
	element := self parser memoizedParse: aStream.
	^element isParseFailure
	    ifFalse: [self block value: element]
	    ifTrue: [element]
! !


PPDelegateParser subclass: #PPFlattenParser
	instanceVariableNames: ''
	category: 'Parser'!


!PPFlattenParser methodsFor: 'parsing'!

parse: aStream
	| start element stop |
	start := aStream position.
	element := self parser memoizedParse: aStream.
	^element isParseFailure
	    ifTrue: [element]
	    ifFalse: [aStream collection 
		copyFrom: start + 1 
		to: aStream position]
! !


PPDelegateParser subclass: #PPSourceParser
	instanceVariableNames: ''
	category: 'Parser'!


!PPSourceParser methodsFor: 'parsing'!

parse: aStream
	| start element stop result |
	start := aStream position.
	element := self parser memoizedParse: aStream.
	^element isParseFailure
		ifTrue: [element]
		ifFalse: [result := aStream collection copyFrom: start + 1 to: aStream position.
			Array with: element with: result].
! !


PPDelegateParser subclass: #PPRepeatingParser
	instanceVariableNames: 'min'
	category: 'Parser'!


!PPRepeatingParser class methodsFor: 'instance creation'!

on: aParser min: aNumber
	    ^self new
		parser: aParser;
		min: aNumber;
		yourself
! !

!PPRepeatingParser methodsFor: 'accessing'!

min
	^min
!

min: aNumber
	min := aNumber
! !

!PPRepeatingParser methodsFor: 'parsing'!

parse: aStream
	| start element elements failure |
	start := aStream position.
	elements := Array new.
	[(elements size < self min) and: [failure isNil]] whileTrue: [
	    element := self parser memoizedParse: aStream.
	    element isParseFailure
			ifFalse: [elements addLast: element]
			ifTrue: [aStream position: start.
				 failure := element]].
	^failure ifNil: [
	    [failure isNil] whileTrue: [
			element := self parser memoizedParse: aStream.
	 		element isParseFailure
				ifTrue: [failure := element]
				ifFalse: [elements addLast: element]].
				elements]
		ifNotNil: [failure].
! !


Object subclass: #PPFailure
	instanceVariableNames: 'position reason'
	category: 'Parser'!


!PPFailure class methodsFor: 'instance creation'!

reason: aString at: anInteger
	    ^self new
		reason: aString at: anInteger;
		yourself
! !

!PPFailure methodsFor: 'accessing'!

position
	^position ifNil: [0]
!

position: aNumber
	position := aNumber
!

reason
	^reason ifNil: ['']
!

reason: aString
	reason := aString
!

reason: aString at: anInteger
	self 
	    reason: aString; 
	    position: anInteger
! !

!PPFailure methodsFor: 'testing'!

isParseFailure
	^true
! !


Object subclass: #SmalltalkParser
	instanceVariableNames: ''
	category: 'Parser'!


!SmalltalkParser class methodsFor: 'instance creation'!

parse: aStream
	    ^self new
		parse: aStream
! !

!SmalltalkParser methodsFor: 'grammar'!

parser
	| method expression separator comment ws identifier keyword className string symbol number literalArray variable reference classReference literal ret methodParser expressionParser keyword unarySelector binarySelector keywordPattern unaryPattern binaryPattern assignment temps blockParamList block expression expressions subexpression statements sequence operand unaryMessage unarySend unaryTail binaryMessage binarySend binaryTail keywordMessage keywordSend keywordPair cascade message jsStatement |
	
	separator := (String cr, String space, String lf, String tab) asChoiceParser.
	comment := ('"' asCharacterParser, ('"' asParser not, PPAnyParser new) star, '"' asCharacterParser) flatten.

	ws := (separator / comment) star.
	
	identifier := ('a-z' asCharacterParser, 'a-zA-Z0-9' asCharacterParser star) flatten.

	keyword := (identifier, ':' asParser) flatten.

	className := ('A-Z' asCharacterParser, 'a-zA-Z0-9' asCharacterParser star) flatten.

	string := '''' asParser, ('''''' asParser / ('''' asParser not, PPAnyParser new)) star flatten, '''' asParser
		==> [:node | ValueNode new value: ((node at: 2) replace: '''''' with: '''')].

	symbol := '#' asParser, 'a-zA-Z0-9' asCharacterParser plus flatten
		==> [:node | ValueNode new value: node second].

	number := ('0-9' asCharacterParser plus, ('.' asParser, '0-9' asCharacterParser plus) optional) flatten
		==> [:node | ValueNode new value: node asNumber].

	literal := PPDelegateParser new.

	literalArray := '#(' asParser, (ws, literal, ws) star, ')' asParser
		==> [:node | ValueNode new value: (Array withAll: (node second collect: [:each | each second value]))].

	variable := identifier ==> [:token | VariableNode new value: token].

	classReference := className ==> [:token | ClassReferenceNode new value: token].

	reference := variable / classReference.

	binarySelector := '+*/=><,@%~-' asCharacterParser plus flatten.

	unarySelector := identifier.

	keywordPattern := (ws, keyword, ws, identifier) plus
		==> [:nodes | Array
				  with: ((nodes collect: [:each | each at: 2]) join: '')
				  with: (nodes collect: [:each | each at: 4])].

	binaryPattern := ws, binarySelector, ws, identifier
		==> [:node | Array with: node second with: (Array with: node fourth)].

	unaryPattern := ws, unarySelector
		==> [:node | Array with: node second with: Array new].
	
	expression := PPDelegateParser new.

	expressions := expression, ((ws, '.' asParser, ws, expression) ==> [:node | node fourth]) star
		==> [:node || result |
		    result := Array with: node first.
		    node second do: [:each | result add: each].
		    result].

	assignment := reference, ws, ':=' asParser, ws, expression
		==> [:node | AssignmentNode new left: node first; right: (node at: 5)].

	ret := '^' asParser, ws, expression, ws, '.' asParser optional
	    ==> [:node | ReturnNode new
			     addNode: node third;
			     yourself].

	temps := '|' asParser, (ws, identifier) star, ws, '|' asParser
		==> [:node | node second collect: [:each | each second]].

	blockParamList := (':' asParser, identifier, ws) plus, '|' asParser
		==> [:node | node first collect: [:each | each second]].

	subexpression := '(' asParser, ws, expression, ws, ')' asParser
		==> [:node | node third].

	statements := (ret ==> [:node | Array with: node]) / (expressions, ws, '.' asParser, ws, ret ==> [:node | node first add: (node at: 5); yourself]) / (expressions , '.' asParser optional ==> [:node | node first]).

	sequence := temps optional, ws, statements optional, ws
		==> [:node | SequenceNode new
				 temps: node first;
				 nodes: node third;
				 yourself].

	block := '[' asParser, ws, blockParamList optional, ws, sequence optional, ws, ']' asParser
		==> [:node |
		    BlockNode new
			parameters: node third;
			addNode: (node at: 5) asBlockSequenceNode].

	operand := literal / reference / subexpression.

	literal parser: number / string / literalArray / symbol / block.

	unaryMessage := ws, unarySelector, ':' asParser not
		==> [:node | SendNode new selector: node second].

	unaryTail := PPDelegateParser new.
	unaryTail parser: (unaryMessage, unaryTail optional
			       ==> [:node |
				   node second
					   ifNil: [node first]
					   ifNotNil: [node second valueForReceiver: node first]]).

	unarySend := operand, unaryTail optional
		==> [:node |
		    node second 
			ifNil: [node first]
			ifNotNil: [node second valueForReceiver: node first]].

	binaryMessage := ws, binarySelector, ws, (unarySend / operand)
		==> [:node |
		    SendNode new
			selector: node second;
			arguments: (Array with: node fourth)].

	binaryTail := PPDelegateParser new.
	binaryTail parser: (binaryMessage, binaryTail optional
				    ==> [:node |
					node second 
					    ifNil: [node first]
					    ifNotNil: [ node second valueForReceiver: node first]]).

	binarySend := unarySend, binaryTail optional
		==> [:node |
		    node second
			ifNil: [node first]
			ifNotNil: [node second valueForReceiver: node first]].

	keywordPair := keyword, ws, binarySend.

	keywordMessage := (ws, keywordPair) plus
		==> [:nodes |
		    SendNode new
			selector: ((nodes collect: [:each | each second first]) join: '');
			arguments: (nodes collect: [:each | each second third])].

	keywordSend := binarySend, keywordMessage
		==> [:node |
		    node second valueForReceiver: node first].

	message := binaryMessage / unaryMessage / keywordMessage.

	cascade := (keywordSend / binarySend), (ws, ';' asParser, message) plus
		==> [:node |
		    node first cascadeNodeWithMessages: 
			(node second collect: [:each | each third])].

	jsStatement := '{' asParser, ws, string, ws, '}' asParser
	    ==> [:node | JSStatementNode new
			     source: node third;
			     yourself].

	expression parser: assignment / cascade / keywordSend / binarySend / jsStatement.

	method := (ws, (keywordPattern / binaryPattern / unaryPattern), ws, sequence optional, ws) withSource
	    ==> [:node |
		MethodNode new
		    selector: node first second first;
		    arguments: node first second second;
		    addNode: node first fourth;
		    source: node second;
		    yourself].
	
	^method, PPEOFParser new ==> [:node | node first]
! !

!SmalltalkParser methodsFor: 'parsing'!

parse: aStream
	^self parser parse: aStream
! !


Object subclass: #Chunk
	instanceVariableNames: 'contents'
	category: 'Parser'!


!Chunk methodsFor: 'accessing'!

contents
	^contents ifNil: ['']
!

contents: aString
	contents := aString
! !

!Chunk methodsFor: 'testing'!

isEmptyChunk
	^false
!

isInstructionChunk
	^false
! !


Chunk subclass: #InstructionChunk
	instanceVariableNames: ''
	category: 'Parser'!


!InstructionChunk methodsFor: 'testing'!

isInstructionChunk
	^true
! !


Chunk subclass: #EmptyChunk
	instanceVariableNames: ''
	category: 'Parser'!


!EmptyChunk methodsFor: 'testing'!

isEmptyChunk
	^true
! !


Object subclass: #ChunkParser
	instanceVariableNames: 'parser separator eof ws chunk emptyChunk instructionChunk'
	category: 'Parser'!


!ChunkParser methodsFor: 'accessing'!

chunk
	^chunk ifNil: [chunk := self ws, ('!!!!' asParser / ('!!' asParser not, PPAnyParser new)) plus flatten, '!!' asParser ==> [:node | Chunk new contents: (node second replace: '!!!!' with: '!!')]]
!

emptyChunk
	^emptyChunk ifNil: [emptyChunk := self separator plus, '!!' asParser, self ws ==> [:node | EmptyChunk new]]
!

eof
	^eof ifNil: [eof := self ws, PPEOFParser new ==> [:node | nil]]
!

parser
	^parser ifNil: [
	    parser := self instructionChunk / self emptyChunk / self chunk / self eof]
!

separator
	^separator ifNil: [separator := (String cr, String space, String lf, String tab) asChoiceParser]
!

ws
	^ws ifNil: [ws := self separator star]
! !

!ChunkParser methodsFor: nil!

instructionChunk
	^instructionChunk ifNil: [
	    instructionChunk := self ws, '!!' asParser, self chunk
	    ==> [:node | InstructionChunk new contents: node last contents]]
! !


Object subclass: #Importer
	instanceVariableNames: 'chunkParser'
	category: 'Parser'!


!Importer methodsFor: 'accessing'!

chunkParser
	^chunkParser ifNil: [chunkParser := ChunkParser new parser]
! !

!Importer methodsFor: 'fileIn'!

import: aStream
	aStream atEnd ifFalse: [
	    | nextChunk |
	    nextChunk := self chunkParser parse: aStream.
	    nextChunk ifNotNil: [
		nextChunk isInstructionChunk 
		    ifTrue: [(Compiler new loadExpression: nextChunk contents)
					 scanFrom: aStream]
		    ifFalse: [Compiler new loadExpression: nextChunk contents].
		self import: aStream]]
! !


Object subclass: #Exporter
	instanceVariableNames: ''
	category: 'Parser'!


!Exporter methodsFor: 'fileout'!

exportCategory: aString
	| stream |
	stream := '' writeStream.
	(Smalltalk current classes 
	    select: [:each | each category = aString])
	    do: [:each | stream nextPutAll: (self export: each)].
	^stream contents
! !

!Exporter methodsFor: 'fileOut'!

export: aClass
	| stream |
	stream := '' writeStream.
	self exportDefinitionOf: aClass on: stream.
	stream nextPutAll: String cr.
	self exportMethodsOf: aClass on: stream.
	stream nextPutAll: String cr.
	self exportMetaDefinitionOf: aClass on: stream.
	self exportMethodsOf: aClass class on: stream.
	stream nextPutAll: String cr.
	^stream contents
! !

!Exporter methodsFor: 'private'!

classNameFor: aClass
	^aClass isMetaclass
	    ifTrue: [aClass instanceClass name, '.klass']
	    ifFalse: [
		aClass isNil
		    ifTrue: ['nil']
		    ifFalse: [aClass name]]
!

exportDefinitionOf: aClass on: aStream
	aStream 
	    nextPutAll: 'smalltalk.addClass(';
	    nextPutAll: '''', (self classNameFor: aClass), ''', ';
	    nextPutAll: 'smalltalk.', (self classNameFor: aClass superclass);
	    nextPutAll: ', ['.
	aClass instVarNames 
	    do: [:each | aStream nextPutAll: '''', each, '''']
	    separatedBy: [aStream nextPutAll: ', '].
	aStream	
	    nextPutAll: '], ''';
	    nextPutAll: aClass category, '''';
	    nextPutAll: ');'.
	aClass comment notEmpty ifTrue: [
	    aStream 
	    	nextPutAll: String cr;
		nextPutAll: 'smalltalk.';
		nextPutAll: (self classNameFor: aClass);
		nextPutAll: '.comment=';
		nextPutAll: 'unescape(''', aClass comment escaped, ''')']
!

exportMetaDefinitionOf: aClass on: aStream
	aClass class instVarNames isEmpty ifFalse: [
	    aStream 
		nextPutAll: 'smalltalk.', (self classNameFor: aClass class);
		nextPutAll: '.iVarNames = ['.
	    aClass class instVarNames
		do: [:each | aStream nextPutAll: '''', each, '''']
		separatedBy: [aStream nextPutAll: ','].
	    aStream nextPutAll: '];', String cr]
!

exportMethodsOf: aClass on: aStream
	aClass methodDictionary keysAndValuesDo: [:key :value |
	    aStream 
		nextPutAll: 'smalltalk.addMethod(', String cr;
		nextPutAll: '''', value selector asSelector, ''',', String cr;
		nextPutAll: 'smalltalk.method({', String cr;
		nextPutAll: 'selector: ''', value selector, ''',', String cr;
		nextPutAll: 'category: ''', value category, ''',', String cr;
		nextPutAll: 'fn: ', value fn compiledSource, ',', String cr;
		nextPutAll: 'source: unescape(''', value source escaped, ''')';
		nextPutAll: '}),', String cr;
		nextPutAll: 'smalltalk.', (self classNameFor: aClass);
		nextPutAll: ');', String cr, String cr]
! !