--- a/PositionableStream.st	Tue Feb 21 02:07:07 1995 +0100
+++ b/PositionableStream.st	Wed Feb 22 02:14:51 1995 +0100
@@ -12,7 +12,7 @@
 
 PeekableStream subclass:#PositionableStream
        instanceVariableNames:'collection position readLimit'
-       classVariableNames:'ErrorDuringFileInSignal'
+       classVariableNames:'ErrorDuringFileInSignal ChunkSeparator'
        poolDictionaries:''
        category:'Streams'
 !
@@ -21,7 +21,7 @@
 COPYRIGHT (c) 1989 by Claus Gittinger
 	      All Rights Reserved
 
-$Header: /cvs/stx/stx/libbasic/PositionableStream.st,v 1.19 1995-02-15 10:27:49 claus Exp $
+$Header: /cvs/stx/stx/libbasic/PositionableStream.st,v 1.20 1995-02-22 01:14:21 claus Exp $
 '!
 
 !PositionableStream class methodsFor:'documentation'!
@@ -42,7 +42,7 @@
 
 version
 "
-$Header: /cvs/stx/stx/libbasic/PositionableStream.st,v 1.19 1995-02-15 10:27:49 claus Exp $
+$Header: /cvs/stx/stx/libbasic/PositionableStream.st,v 1.20 1995-02-22 01:14:21 claus Exp $
 "
 !
 
@@ -66,6 +66,8 @@
 	ErrorDuringFileInSignal := Object errorSignal newSignalMayProceed:true.
 	ErrorDuringFileInSignal nameClass:self message:#errorDuringFileInSignal.
 	ErrorDuringFileInSignal notifierString:'error during fileIn'.
+
+	ChunkSeparator := $!!
     ]
 ! !
 
@@ -74,7 +76,7 @@
 chunkSeparator
     "return the chunk-separation character"
 
-    ^ $!!
+    ^ ChunkSeparator
 ! !
 
 !PositionableStream class methodsFor:'instance creation'!
@@ -235,7 +237,7 @@
      index    "{ Class:SmallInteger }"
      currSize "{ Class:SmallInteger }" |
 
-    sep := self class chunkSeparator.
+    sep := ChunkSeparator.
     theString := String new:500.
     currSize := 500.
     thisChar := self skipSeparators.
@@ -294,7 +296,11 @@
 nextChunkPut:aString
     "put aString as a chunk onto the receiver;
      double all exclamation marks except within primitives and append a 
-     single delimiting exclamation mark at the end."
+     single delimiting exclamation mark at the end.
+     This modification of the chunk format was done to have primitive
+     code more readable. (since it must be edited using the fileBrowser).
+     Its no incompatibility, since inline primitives are an ST/X special
+     anyway."
 
     |sep gotPercent inPrimitive character
      index    "{ Class:SmallInteger }"
@@ -302,7 +308,7 @@
      stop     "{ Class:SmallInteger }"
      next     "{ Class:SmallInteger }"|
 
-    sep := self class chunkSeparator.
+    sep := ChunkSeparator.
     inPrimitive := false.
     gotPercent := false.
     index := 1.
@@ -331,6 +337,7 @@
 	index := next.
 	(index <= endIndex) ifTrue:[
 	    character := aString at:index.
+
 	    (character == $% ) ifTrue:[
 		gotPercent := true
 	    ] ifFalse:[
@@ -353,6 +360,7 @@
 		].
 		gotPercent := false
 	    ].
+
 	    self nextPut:character.
 	    index := index + 1
 	]
@@ -422,14 +430,22 @@
 
 fileInNextChunkNotifying:someone
     "read next chunk, evaluate it and return the result;
-     someone (which is usually some codeView) is notified of errors."
+     someone (which is usually some codeView) is notified of errors.
+     Filein is done as follows:
+	read a chunk
+	if it started with an excla, evaluate it, and let the resulting object
+	fileIn more chunks.
+	This is a nice trick, since the methodsFor: expression evaluates to
+	a ClassCategoryReader which reads and compiles chunks for its class.
+	However, other than methodsFor expressions are possible - you can
+	(in theory) create readers for any syntax.
+    "
 
-    |aString sawExcla sep rslt done|
+    |aString sawExcla rslt done|
 
-    sep := self class chunkSeparator.
     self skipSeparators.
     self atEnd ifFalse:[
-	sawExcla := self peekFor:sep.
+	sawExcla := self peekFor:ChunkSeparator.
 	aString := self nextChunk.
 	aString size ~~ 0 ifTrue:[
 	    rslt := Compiler evaluate:aString notifying:someone.
@@ -448,7 +464,7 @@
 		    done := false.
 		    [done] whileFalse:[
 			aString := self nextChunk.
-			done := aString size == 0 or:[aString isEmpty].
+			done := (aString size == 0) or:[aString isEmpty].
 		    ]
 		] ifFalse:[
 		    rslt := rslt fileInFrom:self notifying:someone
@@ -457,7 +473,6 @@
 	]
     ].
     ^ rslt
-
 !
 
 askForDebug:message