* interp/io.boot (%Reader): New data structure.

	* interp/preparse.lisp (INITIALIZE-PREPARSE): Parameter is now a
	reader.
	(preparse1): Likewise.  Tidy.
	* interp/spad-parser.boot (preparseReadLine): Likewise.
	(preparseReadLine1): Likewise.
	(preparse): Likewise.
	(parseSpadFile): Likewise.
	* interp/spad.lisp (SPAD): Make it a unary function.  Simplify.
	(INITIALIZE): Remove.

4 files changed, 69 insertions, 72 deletions

diff --git a/src/interp/io.boot b/src/interp/io.boot
index f7a35617..a7fe1849 100644
--- a/src/interp/io.boot
+++ b/src/interp/io.boot
@@ -99,3 +99,14 @@ findString(s1,s2,k == 0) ==
   n1 := #s1
   or/[i for i in k..(#s2 - n1) |
         and/[stringChar(s1,j) = stringChar(s2,i+j) for j in 0..(n1-1)]]
+
+--%
+--% Reader
+--%
+structure %Reader ==
+  Record(ins: %InputStream, lines: %List %Line) with
+    readerInput == (.ins)
+    readerLines == (.lines)
+
+makeReader ist ==
+  mk%Reader(ist,nil)
diff --git a/src/interp/preparse.lisp b/src/interp/preparse.lisp
index f0edee7c..175a3f7c 100644
--- a/src/interp/preparse.lisp
+++ b/src/interp/preparse.lisp
@@ -73,20 +73,20 @@
 (DEFPARAMETER TOK NIL)
 (DEFPARAMETER DEFINITION_NAME NIL)
 
-(defun Initialize-Preparse (strm)
+(defun Initialize-Preparse (rd)
   (setq $INDEX 0 |$LineList| nil |$EchoLineStack| nil)
-  (setq |$preparseLastLine| (|readLine| strm)))
+  (setq |$preparseLastLine| (|readLine| (|readerInput| rd))))
  
 (defvar $skipme)
  
-(defun |preparse1| (LineList)
- (PROG ((|$LineList| LineList) |$EchoLineStack| NUM A I L PSLOC
+(defun |preparse1| (rd)
+ (PROG ((|$LineList| (|readerLines| rd)) |$EchoLineStack| NUM A I L PSLOC
         INSTRING PCOUNT COMSYM STRSYM OPARSYM CPARSYM N NCOMSYM
         (SLOC -1) (CONTINUE NIL)  (PARENLEV 0) (NCOMBLOCK ())
         (LINES ()) (LOCS ()) (NUMS ()) functor  )
- READLOOP (DCQ (NUM . A) (|preparseReadLine| LineList))
+ READLOOP (DCQ (NUM . A) (|preparseReadLine| rd))
          (cond ((|atEndOfUnit?| A)
-                (|preparseEcho| LineList)
+                (|preparseEcho| (|readerLines| rd))
                 (COND ((NULL LINES) (RETURN NIL))
                       (NCOMBLOCK
                        (|findCommentBlock| NIL NUMS LOCS NCOMBLOCK NIL)))
@@ -94,7 +94,7 @@
 			 (|parsePiles| (|reverse!| LOCS) (|reverse!| LINES))))))
          (cond ((and (NULL LINES) (> (LENGTH A) 0) (EQ (CHAR A 0) #\) ))
                 ; this is a command line, don't parse it
-                (|preparseEcho| LineList)
+                (|preparseEcho| (|readerLines| rd))
                 (setq |$preparseLastLine| nil) ;don't reread this line
                 (SETQ LINE a)
                 (CATCH 'SPAD_READER (|doSystemCommand| (subseq LINE 1)))
@@ -125,7 +125,7 @@
                 (COND
                   ((= SLOC N)
                    (COND ((AND NCOMBLOCK (NOT (= N (CAR NCOMBLOCK))))
-                          (|findCommentBlock| NUM NUMS LOCS NCOMBLOCK linelist)
+                          (|findCommentBlock| NUM NUMS LOCS NCOMBLOCK  (|readerLines| rd))
                           (SETQ NCOMBLOCK NIL)))
                    (SETQ NCOMBLOCK (CONS N (CONS A (IFCDR NCOMBLOCK))))
                    (SETQ A ""))
@@ -157,8 +157,8 @@
 		      (setq $skipme nil))))
          (when (and LINES (EQL SLOC 0))
              (IF (AND NCOMBLOCK (NOT (ZEROP (CAR NCOMBLOCK))))
-               (|findCommentBlock| NUM NUMS LOCS NCOMBLOCK linelist))
-             (IF (NOT (|ioTerminal?| in-stream))
+               (|findCommentBlock| NUM NUMS LOCS NCOMBLOCK (|readerLines| rd)))
+             (IF (NOT (|ioTerminal?| (|readerInput| rd)))
                  (setq |$preparseLastLine|
                        (|reverse!| |$EchoLineStack|)))
              (RETURN (|pairList| (|reverse!| NUMS)
@@ -168,14 +168,14 @@
 		(setq SLOC PSLOC)
 		(GO REREAD)))
          (COND (NCOMBLOCK
-                (|findCommentBlock| NUM NUMS LOCS NCOMBLOCK linelist)
+                (|findCommentBlock| NUM NUMS LOCS NCOMBLOCK (|readerLines| rd))
                 (setq NCOMBLOCK ())))
          (PUSH SLOC LOCS)
- REREAD  (|preparseEcho| LineList)
+ REREAD  (|preparseEcho| (|readerLines| rd))
          (PUSH A LINES)
          (PUSH NUM NUMS)
          (setq PARENLEV (+ PARENLEV PCOUNT))
-         (when (and (|ioTerminal?| in-stream) (not continue))
+         (when (and (|ioTerminal?| (|readerInput| rd)) (not continue))
 	   (setq |$preparseLastLine| nil)
 	   (RETURN (|pairList| (|reverse!| NUMS)
 		    (|parsePiles| (|reverse!| LOCS) (|reverse!| LINES)))))
diff --git a/src/interp/spad-parser.boot b/src/interp/spad-parser.boot
index ff9051ed..56815de0 100644
--- a/src/interp/spad-parser.boot
+++ b/src/interp/spad-parser.boot
@@ -78,29 +78,29 @@ indentationLocation line ==
     tabChar? line.i => loc := 8 * (loc quo 8 + 1)
     return loc
 
-skipIfBlock x ==
-  [n,:line] := z := preparseReadLine1 x
+skipIfBlock rs ==
+  [n,:line] := z := preparseReadLine1 rs
   not string? line => z
-  #line = 0 => skipIfBlock x
+  #line = 0 => skipIfBlock rs
   line.0 = char ")" =>
     stringPrefix?('")if",line) =>
-      EVAL string2BootTree storeBlanks!(line,2) => preparseReadLine x
-      skipIfBlock x
+      EVAL string2BootTree storeBlanks!(line,2) => preparseReadLine rs
+      skipIfBlock rs
     stringPrefix?('")elseif",line) =>
-      EVAL string2BootTree storeBlanks!(line,7) => preparseReadLine x
-      skipIfBlock x
+      EVAL string2BootTree storeBlanks!(line,7) => preparseReadLine rs
+      skipIfBlock rs
     stringPrefix?('")else",line) or stringPrefix?('")endif",line) =>
-      preparseReadLine x
+      preparseReadLine rs
     stringPrefix?('")fin",line) => [n,:%nothing]
-    skipIfBlock x
-  skipIfBlock x
+    skipIfBlock rs
+  skipIfBlock rs
 
-skipToEndif x ==
-  [n,:line] := z := preparseReadLine1 x
+skipToEndif rs ==
+  [n,:line] := z := preparseReadLine1 rs
   not string? line => z
-  stringPrefix?(line,'")endif") => preparseReadLine x
+  stringPrefix?(line,'")endif") => preparseReadLine rs
   stringPrefix?(line,'")fin") => [n,:%nothing]
-  skipToEndif x
+  skipToEndif rs
 
 ++ `n' is the line number of the current line
 ++ `oldnums' is the list of line numbers of previous lines
@@ -118,25 +118,25 @@ findCommentBlock(n,oldnums,oldlocs,ncblock,lines) ==
        :reverse block]
   $COMBLOCKLIST := [x,:$COMBLOCKLIST]
 
-preparseReadLine x ==
-  [n,:line] := z := preparseReadLine1 x
+preparseReadLine rs ==
+  [n,:line] := z := preparseReadLine1 rs
   not string? line or #line = 0 => z
   line.0 = char ")" =>
     stringPrefix?('")if",line) =>
-      EVAL string2BootTree storeBlanks!(line,3) => preparseReadLine x
-      skipIfBlock x
+      EVAL string2BootTree storeBlanks!(line,3) => preparseReadLine rs
+      skipIfBlock rs
     stringPrefix?('")elseif",line) or stringPrefix?('")else",line) =>
-      skipToEndif x
-    stringPrefix?('")endif",line) => preparseReadLine x
+      skipToEndif rs
+    stringPrefix?('")endif",line) => preparseReadLine rs
     stringPrefix?('")fin",line) => [n,:%nothing]
     z
   z
 
-preparseReadLine1 x ==
+preparseReadLine1 rs ==
   if $LineList then
     [line,:$LineList] := $LineList
   else
-    line := expandLeadingTabs readLine IN_-STREAM
+    line := expandLeadingTabs readLine readerInput rs
   $preparseLastLine := line
   not string? line => [$INDEX]
   $INDEX := $INDEX + 1
@@ -144,7 +144,7 @@ preparseReadLine1 x ==
   $EchoLineStack := [copyString line,:$EchoLineStack]
   n := $INDEX
   if #line > 0 and line.maxIndex(line) = char "__" then
-    line := strconc(subString(line,0,maxIndex line),rest preparseReadLine1 x)
+    line := strconc(subString(line,0,maxIndex line),rest preparseReadLine1 rs)
     $preparseLastLine := line
   [n,:line]
 
@@ -200,17 +200,17 @@ parsePrint l ==
     formatToStdout '"~%"
   nil
 
-preparse st ==
+preparse rd ==
   $COMBLOCKLIST := nil
   $SKIPME := false
-  stack := 
+  readerLines(rd) := 
     $preparseLastLine =>
       $preparseLastLine is [.,:.] => $preparseLastLine
       [$preparseLastLine]
     nil
-  $INDEX := $INDEX - #stack
-  u := preparse1 stack
-  $SKIPME => preparse st
+  $INDEX := $INDEX - #readerLines rd
+  u := preparse1 rd
+  $SKIPME => preparse rd
   parsePrint u
   $headerDocumentation := nil
   $docList := nil
@@ -981,26 +981,26 @@ parseSpadFile sourceFile ==
     -- we need to restore the global input stream state after we
     -- finished messing with it.
     IN_-STREAM: local := MAKE_-INSTREAM sourceFile
+    rd := makeReader IN_-STREAM
 
     -- If soureFile cannot be processed for whatever reasons
     -- get out of here instead of being stuck later.
-    IN_-STREAM = nil =>
-      systemError '"cannot open input source file"
-    INITIALIZE_-PREPARSE IN_-STREAM
+    readerInput rd = nil => systemError '"cannot open input source file"
+    INITIALIZE_-PREPARSE rd
 
     -- gather parse trees for all toplevel expressions in sourceFile.
     asts := []                                   
-    while not eof? IN_-STREAM repeat
-      $lineStack: local := preparse IN_-STREAM
+    while not eof? readerInput rd repeat
+      $lineStack: local := preparse rd
       $lineStack = nil => leave nil -- explicit end of input
       LINE: local := CDAR $lineStack
-      CATCH('SPAD__READER,parseNewExpr())
+      CATCH($SpadReaderTag,parseNewExpr())
       asts := [parseTransform postTransform popStack1(), :asts]
     -- we accumulated the parse trees in reverse order
     reverse! asts
   finally                      -- clean up the mess, and get out of here
     ioClear!()
-    SHUT IN_-STREAM                              
+    SHUT readerInput rd
 
 --%
 
diff --git a/src/interp/spad.lisp b/src/interp/spad.lisp
index 7776a6e6..e0ccf4be 100644
--- a/src/interp/spad.lisp
+++ b/src/interp/spad.lisp
@@ -64,17 +64,15 @@
   (|nextLinesClear!|)
   (|ioClear!|))
 
-(defun spad (&optional
-              (*spad-input-file* nil)
-              (*spad-output-file* nil)
+(defun spad (ifile
              &aux
            (*comp370-apply* (function |printBackendDecl|))
            (*fileactq-apply* (function |printBackendDecl|))
            ($SPAD T)
            (OPTIONLIST nil)
            (*EOF* NIL)
-           (|$editFile| *spad-input-file*)
-           in-stream out-stream)
+           (|$editFile| ifile)
+           rd in-stream out-stream)
   (declare (special |$Echo| |$editFile| *comp370-apply* *EOF*))
   (setq |$InteractiveMode| nil)
   ;; only rebind |$InteractiveFrame| if compiling
@@ -88,22 +86,15 @@
   (init-boot/spad-reader)
   (unwind-protect
     (progn
-      (setq in-stream (if *spad-input-file*
-                         (open *spad-input-file* :direction :input)
-			|$InputStream|))
-      (initialize-preparse in-stream)
-      (setq out-stream (if *spad-output-file*
-                           (open *spad-output-file* :direction :output)
-                         |$OutputStream|))
-      (when *spad-output-file*
-         (format out-stream "~&;;; -*- Mode:Lisp; Package:Boot  -*-~%~%")
-         (print-package "BOOT"))
-      (setq |$OutputStream| out-stream)
+      (setq in-stream (open ifile :direction :input))
+      (setq rd (|makeReader| in-stream))
+      (initialize-preparse rd)
+      (setq out-stream |$OutputStream|)
       (loop
        (if (|eof?| in-stream) (return nil))
-       (catch 'SPAD_READER
+       (catch |$SpadReaderTag|
 	 (progn 
-	   (setq |$lineStack| (|preparse| in-stream))
+	   (setq |$lineStack| (|preparse| rd))
 	   (when (null |$lineStack|)
 	     (return nil))
 	   (when |$lineStack|
@@ -117,8 +108,7 @@
                        (format out-stream "~&")))
                ))))
       (|ioClear!|)))
-    (if *spad-input-file* (shut in-stream))
-    (if *spad-output-file* (shut out-stream)))
+    (shut in-stream))
   T))
 
 (DEFUN INTEGER-BIT (N I) (LOGBITP I N))
@@ -170,10 +160,6 @@
          (if |$InteractiveMode| (|spadThrow|))
          (|translateSpad| x))))
 
-(defun INITIALIZE () 
-  (init-boot/spad-reader)
-  (initialize-preparse |$InputStream|))
-
 (defmacro try (X)
   `(LET ((|$autoLine|))
         (declare (special |$autoLine|))