--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/compiler/PPCScanner.st	Fri Jul 24 15:06:54 2015 +0100
@@ -0,0 +1,80 @@
+"{ Package: 'stx:goodies/petitparser/compiler' }"
+
+"{ NameSpace: Smalltalk }"
+
+Object subclass:#PPCScanner
+	instanceVariableNames:'matches stream maxPriority currentChar'
+	classVariableNames:''
+	poolDictionaries:''
+	category:'PetitCompiler-Scanner'
+!
+
+!PPCScanner methodsFor:'accessing'!
+
+stream
+    ^ stream
+!
+
+stream: anObject
+    stream := anObject
+! !
+
+!PPCScanner methodsFor:'as yet unclassified'!
+
+recordMatch: match 
+ 	^ self recordMatch: match priority: 0
+!
+
+recordMatch: match priority: currentPriority
+    (maxPriority < currentPriority) ifTrue: [ 
+        matches := IdentityDictionary new.
+        maxPriority := currentPriority.
+    ].
+         
+    (maxPriority == currentPriority) ifTrue: [ 
+     	matches at: match put: stream position
+ 	].
+!
+
+return
+    ^ self returnPriority: SmallInteger minVal.
+!
+
+returnPriority: priority
+    (maxPriority < priority) ifTrue: [ 
+        ^ IdentityDictionary new
+    ].
+    ^ matches keysAndValuesRemove: [ :key :value | key class == PEGFsaFailure ]
+! !
+
+!PPCScanner methodsFor:'initialization'!
+
+initialize
+    super initialize.
+    matches := IdentityDictionary new.	
+    maxPriority := SmallInteger minVal.
+! !
+
+!PPCScanner methodsFor:'scanning'!
+
+consumeConditionally: character
+    ^ (stream peek == character) ifTrue: [ stream next. true ] ifFalse: [ false ]
+!
+
+next
+    stream next
+!
+
+peek
+    ^ currentChar
+!
+
+peekBetween: start and: stop
+    (currentChar == nil) ifTrue: [ ^ false ].
+    ^ start <= currentChar codePoint and: [ currentChar codePoint <= stop ]
+!
+
+step
+    currentChar := stream next
+! !
+