"{ Package: 'stx:goodies/petitparser' }"

PPDelegateParser subclass:#PPCompositeParser

	instanceVariableNames:''

	classVariableNames:''

	poolDictionaries:''

	category:'PetitParser-Tools'

!

!PPCompositeParser class methodsFor:'instance creation'!

new

	"Answer a new parser starting at the default start symbol."

	^ self newStartingAt: self startSymbol

!

newStartingAt: aSymbol

	"Answer a new parser starting at aSymbol."

	^ self basicNew initializeStartingAt: aSymbol

! !

!PPCompositeParser class methodsFor:'accessing'!

ignoredNames

	"Answer a collection of instance-variables that should not be automatically initialized with productions, but that are used internal to the composite parser."

	^ PPCompositeParser allInstVarNames

!

startSymbol

	"Answer the method that represents the default start symbol."

	^ #start

! !

!PPCompositeParser class methodsFor:'parsing'!

parse: anObject

	^ self parse: anObject startingAt: self startSymbol

!

parse: anObject onError: aBlock

	^ self parse: anObject startingAt: self startSymbol onError: aBlock

!

parse: anObject startingAt: aSymbol

	^ (self newStartingAt: aSymbol) parse: anObject

!

parse: anObject startingAt: aSymbol onError: aBlock

	^ (self newStartingAt: aSymbol) parse: anObject onError: aBlock

! !

!PPCompositeParser methodsFor:'accessing'!

start

	"Answer the production to start this parser with."

	self subclassResponsibility

! !

!PPCompositeParser methodsFor:'initialization'!

initializeStartingAt: aSymbol

	| allVariableNames ignoredVariableNames productionIndexesAndNames |

	self initialize.	

	"find all the productions that need to be initialized"

	allVariableNames := self class allInstVarNames

		collect: [ :each | each asSymbol ].

	ignoredVariableNames := self class ignoredNames

		collect: [ :each | each asSymbol ].

	productionIndexesAndNames := ((1 to: self class instSize)

		collect: [ :index | index -> (allVariableNames at: index) ])

		reject: [ :assoc | ignoredVariableNames includes: assoc value ].

	"initialize productions with an undefined parser to be replaced later"

	parser := PPUnresolvedParser named: aSymbol.

	productionIndexesAndNames do: [ :assoc |

		self instVarAt: assoc key put: (PPUnresolvedParser named: assoc value) ].

	parser def: (self perform: aSymbol).

	"resolve unresolved parsers with their actual implementation"

	productionIndexesAndNames do: [ :assoc |

		(self respondsTo: assoc value)

			ifFalse: [ self error: 'Unable to initialize ' , assoc value printString ]

			ifTrue: [ (self instVarAt: assoc key) def: (self perform: assoc value) ] ]

! !

!PPCompositeParser methodsFor:'querying'!

productionAt: aSymbol

	"Answer the production named aSymbol."

	^ self productionAt: aSymbol ifAbsent: [ nil ]

!

productionAt: aSymbol ifAbsent: aBlock

	"Answer the production named aSymbol, if there is no such production answer the result of evaluating aBlock."

	(self class ignoredNames includes: aSymbol asString)

		ifTrue: [ ^ aBlock value ].

	(self class startSymbol = aSymbol)

		ifTrue: [ ^ parser ].

	^ self instVarAt: (self class allInstVarNames

		indexOf: aSymbol asString

		ifAbsent: [ ^ aBlock value ])

! !

!PPCompositeParser class methodsFor:'documentation'!

version

    ^ '$Header: /cvs/stx/stx/goodies/petitparser/PPCompositeParser.st,v 1.3 2012-05-04 22:02:49 vrany Exp $'

!

version_CVS

    ^ '$Header: /cvs/stx/stx/goodies/petitparser/PPCompositeParser.st,v 1.3 2012-05-04 22:02:49 vrany Exp $'

!

version_SVN

    ^ '§Id: PPCompositeParser.st 2 2010-12-17 18:44:23Z vranyj1 §'

! !