FoStrings update

Data/Texts/en.dat

@@ -0,0 +1,190 @@
+0 "undeclared identifier"
+1 "multiply defined identifier"
+2 "illegal character in number"
+3 "illegal character in string"
+4 "identifier does not match procedure name"
+5 "comment not closed"
+11 '"=" expected'
+12 "type definition starts with incorrect symbol"
+13 "factor starts with incorrect symbol"
+14 "statement starts with incorrect symbol"
+15 "declaration followed by incorrect symbol"
+16 "MODULE expected"
+20 '"." missing'
+21 '"," missing'
+22 '":" missing'
+24 '")" missing'
+25 '"]" missing'
+26 '"}" missing'
+27 "OF missing"
+28 "THEN missing"
+29 "DO missing"
+30 "TO missing"
+32 '"(" missing'
+33 "CONST, TYPE, VAR, PROCEDURE, BEGIN, or END missing"
+34 "PROCEDURE, BEGIN, or END missing"
+35 '"," or OF expected'
+36 '":=" missing'
+39 "this is not a VAR-parameter"
+40 "identifier expected"
+41 '";" missing'
+42 '"@" missing'
+43 "END missing"
+46 "UNTIL missing"
+47 "EXIT not within loop statement"
+48 "illegally marked identifier"
+49 "incorrect use of RETURN"
+50 "expression should be constant"
+51 "constant not an integer"
+52 "identifier does not denote a type"
+53 "identifier does not denote a record type"
+54 "result type of procedure is not a basic type"
+55 "procedure call of a function"
+56 "assignment to non-variable"
+57 "pointer not bound to record or array type"
+58 "recursive type definition"
+59 "illegal open array parameter"
+60 "wrong type of case label"
+61 "inadmissible type of case label"
+62 "case label defined more than once"
+63 "illegal value of constant"
+64 "more actual than formal parameters"
+65 "fewer actual than formal parameters"
+66 "element types of actual array and formal open array differ"
+67 "actual parameter corresponding to open array is not an array"
+68 "control variable must be integer"
+69 "parameter must be an integer constant"
+70 "pointer or VAR / IN record required as formal receiver"
+71 "pointer expected as actual receiver"
+72 "procedure must be bound to a record of the same scope"
+73 "procedure must have level 0"
+74 "procedure unknown in base type"
+75 "invalid call of base procedure"
+76 "this variable (field) is read only"
+77 "object is not a record"
+78 "dereferenced object is not a variable"
+79 "indexed object is not a variable"
+80 "index expression is not an integer"
+81 "index out of specified bounds"
+82 "indexed variable is not an array"
+83 "undefined record field"
+84 "dereferenced variable is not a pointer"
+85 "guard or test type is not an extension of variable type"
+86 "guard or testtype is not a pointer"
+87 "guarded or tested variable is neither a pointer nor a VAR- or IN-parameter record"
+88 "open array not allowed as variable, record field or array element"
+90 "dereferenced variable is not a character array"
+91 "control variable must be local"
+92 "operand of IN not an integer, or not a set"
+93 "set element type is not an integer"
+94 "operand of & is not of type BOOLEAN"
+95 "operand of OR is not of type BOOLEAN"
+96 "operand not applicable to (unary) +"
+97 "operand not applicable to (unary) -"
+98 "operand of ~ is not of type BOOLEAN"
+99 "ASSERT fault"
+100 "incompatible operands of dyadic operator"
+101 "operand type inapplicable to *"
+102 "operand type inapplicable to /"
+103 "operand type inapplicable to DIV"
+104 "operand type inapplicable to MOD"
+105 "operand type inapplicable to +"
+106 "operand type inapplicable to -"
+107 "operand type inapplicable to = or #"
+108 "operand type inapplicable to relation"
+110 "operand is not a type"
+111 "operand inapplicable to (this) function"
+112 "operand is not a variable"
+113 "incompatible assignment"
+114 "string too long to be assigned"
+115 "parameter doesn't match"
+116 "number of parameters doesn't match"
+117 "result type doesn't match"
+118 "export mark doesn't match with forward declaration"
+119 "redefinition textually precedes procedure bound to base type"
+120 "type of expression following IF, WHILE, UNTIL or ASSERT is not BOOLEAN"
+121 "called object is not a procedure (or is an interrupt procedure)"
+122 "actual VAR-, IN-, or OUT-parameter is not a variable"
+123 "type is not identical with that of formal VAR-, IN-, or OUT-parameter"
+124 "type of result expression differs from that of procedure"
+125 "type of case expression is neither INTEGER nor CHAR"
+126 "this expression cannot be a type or a procedure"
+127 "illegal use of object"
+128 "unsatisfied forward reference"
+129 "unsatisfied forward procedure"
+130 "WITH clause does not specify a variable"
+131 "LEN not applied to array"
+132 "dimension in LEN too large or negative"
+133 "system flag doesn't match forward declaration"
+135 "SYSTEM not imported"
+136 "LEN applied to untagged array"
+137 "unknown array length"
+138 "NEW not allowed for untagged structures"
+139 "test applied to untagged record"
+140 "operand type inapplicable to DIV0"
+141 "operand type inapplicable to REM0"
+145 "untagged open array not allowed as value parameter"
+150 "key inconsistency of imported module"
+151 "incorrect symbol file"
+152 "symbol file of imported module not found"
+153 "object or symbol file not opened (disk full?)"
+154 "recursive import not allowed"
+155 "generation of new symbol file not allowed"
+156 "default target machine address size and alignment used"
+157 "syntax error in parameter file"
+177 "IN only allowed for records and arrays"
+178 "illegal attribute"
+179 "abstract methods of exported records must be exported"
+180 "illegal receiver type"
+181 "base type is not extensible"
+182 "base procedure is not extensible"
+183 "non-matching export"
+184 "attribute does not match with forward declaration"
+185 "missing NEW attribute"
+186 "illegal NEW attribute"
+187 "new empty procedure in non extensible record"
+188 "extensible procedure in non extensible record"
+189 "illegal attribute change"
+190 "record must be abstract"
+191 "base type must be abstract"
+192 "unimplemented abstract procedures in base types"
+193 "abstract or limited records may not be allocated"
+194 "no supercall allowed to abstract or empty procedures"
+195 "empty procedures may not have out parameters or return a value"
+196 "procedure is implement-only exported"
+197 "extension of limited type must be limited"
+200 "not yet implemented"
+201 "lower bound of set range greater than higher bound"
+202 "set element greater than MAX(SET) or less than 0"
+203 "number too large"
+204 "product too large"
+205 "division by zero"
+206 "sum too large"
+207 "difference too large"
+208 "overflow in arithmetic shift"
+209 "case range too large"
+210 "overflow in logical shift"
+213 "too many cases in case statement"
+214 "name collision"
+218 "illegal value of parameter (0 <= p < 256)"
+220 "illegal value of parameter"
+221 "too many pointers in a record"
+222 "too many global pointers"
+223 "too many record types"
+225 "address of pointer variable too large (move forward in text)"
+226 "too many exported procedures"
+227 "too many imported modules"
+228 "too many exported structures"
+229 "too many nested records for import"
+230 "too many constants (strings) in module"
+231 "too many link table entries (external procedures)"
+232 "too many commands in module"
+233 "record extension hierarchy too high"
+234 "export of recursive type not allowed"
+240 "identifier too long"
+241 "string too long"
+242 "address overflow"
+243 "concatenation of module, type, and guarded variable exceeds maximum name length"
+244 "cyclic type definition not allowed"
+265 "unsupported string operation"
+401 "file contains wrong module name"

src/Data/Fonts/Main.ofi

@@ -1,3 +0,0 @@
-mono
-8 16
-lata box cyr

src/FoStrings.Mod

@@ -1,13 +1,13 @@
 MODULE FoStrings;
-IMPORT Strings, Int;
+IMPORT Strings, Texts, Int, Out;
+
+VAR lang: ARRAY 6 OF CHAR;
 
 PROCEDURE GetErrorStr*(err: INTEGER; VAR s: ARRAY OF CHAR);
 BEGIN
   IF err = 41 THEN s := 'Пропущена точка с запятой.'
-  ELSE
-    s := 'Ошибка ';
-    Int.Append(err, s);
-    Strings.Append('.', s)
+  ELSIF err = 257 THEN s := 'Файл содержит неверное имя модуля.'
+  ELSE s := 'Текст '; Int.Append(err, s); Strings.Append('-й ошибки.', s)
   END
 END GetErrorStr;
 
@@ -21,4 +21,25 @@ BEGIN
   Strings.Append(z, s)
 END MakeErrorStr;
 
+PROCEDURE LoadStrings;
+VAR T: Texts.Text;
+  S: Texts.Scanner;
+  fname: ARRAY 256 OF CHAR;
+BEGIN
+  fname := 'Data/Texts/'; Strings.Append(lang, fname);
+  Strings.Append('.dat', fname);
+  NEW(T); Texts.Open(T, fname);
+  Texts.OpenScanner(S, T, 0);
+  Texts.Scan(S);
+  IF S.class = Texts.Int THEN
+    Out.String('READ INTEGER '); Out.Int(S.i, 0); Out.Ln
+  ELSE
+    Out.String('READ CLASS '); Out.Int(S.class, 0); Out.Ln
+  END
+END LoadStrings;
+
+PROCEDURE SetLang*(language: ARRAY OF CHAR);
+BEGIN lang := language; LoadStrings
+END SetLang;
+
 END FoStrings.

src/FreeOberon.Mod

@@ -694,15 +694,21 @@ BEGIN last := ch; Files.ReadChar(R, ch);
   WHILE ~R.eof & (ch <= ' ') DO Files.ReadChar(R, ch) END
 END SkipComment;
 
-PROCEDURE GetSym(VAR R: Files.Rider; VAR ch: CHAR; VAR s: ARRAY OF CHAR);
+PROCEDURE ReadCh(VAR R: Files.Rider; VAR ch: CHAR; VAR line, col: INTEGER);
+BEGIN Files.ReadChar(R, ch);
+  IF ch = 0AX THEN INC(line); col := 1 ELSE INC(col) END
+END ReadCh;
+
+PROCEDURE GetSym(VAR R: Files.Rider; VAR ch: CHAR; VAR s: ARRAY OF CHAR;
+    VAR line, col: INTEGER);
 VAR i: INTEGER;
 BEGIN
-  WHILE ~R.eof & (ch <= ' ') DO Files.ReadChar(R, ch) END;
+  WHILE ~R.eof & (ch <= ' ') DO ReadCh(R, ch, line, col) END;
   i := 0;
   IF ~R.eof THEN
     IF ch = '(' THEN
-      Files.ReadChar(R, ch);
-      IF ch = '*' THEN Files.ReadChar(R, ch); SkipComment(R, ch, s)
+      ReadCh(R, ch, line, col);
+      IF ch = '*' THEN ReadCh(R, ch, line, col); SkipComment(R, ch, s)
       ELSE s[i] := ch; INC(i)
       END
     END;
@@ -711,49 +717,63 @@ BEGIN
             (('A' <= CAP(ch)) & (CAP(ch) <= 'Z') OR
              ('0' <= ch) & (ch <= '9')) DO
         IF i < LEN(s) - 1 THEN s[i] := ch; INC(i) END;
-        Files.ReadChar(R, ch)
+        ReadCh(R, ch, line, col)
       END
     ELSE
       WHILE ~R.eof & (ch > ' ') &
             ~(('A' <= CAP(ch)) & (CAP(ch) <= 'Z') OR
               ('0' <= ch) & (ch <= '9')) DO
         IF i < LEN(s) - 1 THEN s[i] := ch; INC(i) END;
-        Files.ReadChar(R, ch)
+        ReadCh(R, ch, line, col)
       END
     END
   END;
   s[i] := 0X
 END GetSym;
 
-PROCEDURE GetImportedModules(IN fname: ARRAY OF CHAR;
-    VAR ok: BOOLEAN): StrList;
+(** Returns true if the two module names are equal.
+  modname is the identifier that comes after the keyword MODULE.
+  filebase is the file name without the extension; on Windows it
+  is allowed to be written in different case. *)
+PROCEDURE EqualModuleNames(modname, filebase: ARRAY OF CHAR): BOOLEAN;
+BEGIN IF Config.isWindows THEN Strings.Cap(modname); Strings.Cap(filebase) END;
+RETURN modname = filebase END EqualModuleNames;
+
+PROCEDURE GetImportedModules(IN fname, modname: ARRAY OF CHAR;
+    VAR ok: BOOLEAN; VAR line, col: INTEGER): StrList;
 VAR F: Files.File;
   R: Files.Rider;
   top, p: StrList;
   ch: CHAR;
   mod, s, fname2: ARRAY 256 OF CHAR;
   exit: BOOLEAN;
-BEGIN NEW(top); top.next := NIL; p := top;
+BEGIN ok := FALSE; NEW(top); top.next := NIL; p := top;
   F := Files.Old(fname);
   IF F # NIL THEN
-    Files.Set(R, F, 0); Files.ReadChar(R, ch); GetSym(R, ch, s);
-    ok := s = 'MODULE'; GetSym(R, ch, s); GetSym(R, ch, s); (*!FIXME check module name*)
-    IF ok THEN
-      ok := s = ';'; GetSym(R, ch, s);
-      IF ok THEN
-        ok := s = 'IMPORT'; GetSym(R, ch, s); exit := FALSE;
-        WHILE ~exit & ('A' <= CAP(s[0])) & (CAP(s[0]) <= 'Z') DO
-          mod := s; GetSym(R, ch, s); fname2[0] := 0X;
-          IF s = ':=' THEN GetSym(R, ch, s); mod := s; GetSym(R, ch, s) END;
-          IF IsSysModule(mod) OR FindModule(mod, fname2) THEN
-            NEW(p.next); p := p.next; p.next := NIL;
-            p.s := mod$; p.fname := fname2$
-          END;
-          IF s = ',' THEN GetSym(R, ch, s) ELSE exit := FALSE END
+    Files.Set(R, F, 0); Files.ReadChar(R, ch);
+    line := 1; col := 1; GetSym(R, ch, s, line, col);
+    IF s = 'MODULE' THEN GetSym(R, ch, s, line, col);
+      IF EqualModuleNames(modname, s) THEN
+        GetSym(R, ch, s, line, col);
+        IF s = ';' THEN GetSym(R, ch, s, line, col); ok := TRUE;
+          IF s = 'IMPORT' THEN GetSym(R, ch, s, line, col); exit := FALSE;
+            WHILE ~exit & ('A' <= CAP(s[0])) & (CAP(s[0]) <= 'Z') DO
+              mod := s; GetSym(R, ch, s, line, col); fname2[0] := 0X;
+              IF s = ':=' THEN GetSym(R, ch, s, line, col);
+                mod := s; GetSym(R, ch, s, line, col)
+              END;
+              IF IsSysModule(mod) OR FindModule(mod, fname2) THEN
+                NEW(p.next); p := p.next; p.next := NIL;
+                p.s := mod$; p.fname := fname2$
+              END;
+              IF s = ',' THEN GetSym(R, ch, s, line, col)
+              ELSE exit := FALSE
+              END
+            END
+          END
         END
       END
     END
-  ELSE ok := FALSE
   END ;
 RETURN top.next END GetImportedModules;
 
@@ -775,18 +795,22 @@ BEGIN
   END
 END AddUniqueToList;
 
-PROCEDURE UsedModuleList(IN modname, fname: ARRAY OF CHAR): StrList;
+PROCEDURE UsedModuleList(IN modname, fname: ARRAY OF CHAR;
+    VAR ok: BOOLEAN; VAR errFname: ARRAY OF CHAR;
+    VAR errLine, errCol: INTEGER): StrList;
 VAR res, list, list2, p: StrList;
-  ok: BOOLEAN;
 BEGIN res := NIL; ok := TRUE;
   IF ~IsSysModule(modname) THEN
-    list := GetImportedModules(fname, ok); p := list;
+    list := GetImportedModules(fname, modname, ok, errLine, errCol); p := list;
     IF ok THEN
-      WHILE p # NIL DO
-        list2 := UsedModuleList(p.s, p.fname);
+      WHILE ok & (p # NIL) DO
+        list2 := UsedModuleList(p.s, p.fname, ok, errFname, errLine, errCol);
         AddUniqueToList(list2, res);
         p := p.next
       END
+    ELSE
+      Strings.Copy(fname, errFname);
+      Out.String('Не могу разобраться с '); Out.String(modname); Out.Ln
     END
   END;
   IF ok THEN
@@ -812,9 +836,12 @@ BEGIN i := 0; j := 0;
 END GetModuleName;
 
 PROCEDURE OnBuild(c: OV.Control);
-VAR w: OV.Window; graph: BOOLEAN;
-  mainFname, modname, exename: ARRAY 256 OF CHAR;
+VAR w: OV.Window;
+  graph, ok: BOOLEAN;
+  mainFname, modname, exename, errFname, s: ARRAY 256 OF CHAR;
+  errLine, errCol: INTEGER;
   modules: StrList;
+  e: Editor.Editor;
 BEGIN w := c.app.windows;
   IF (w # NIL) & (w IS Editor.Editor) THEN
     IF Editor.TextChanged(w(Editor.Editor)) THEN FileSave(c) END;
@@ -822,13 +849,22 @@ BEGIN w := c.app.windows;
       mainFname := w(Editor.Editor).fname$;
       SetWorkDir(mainFname);
       GetModuleName(mainFname, modname);
-      modules := UsedModuleList(modname, mainFname);
-      graph := ImportsGraph(modules);
-      needWindowed := graph;
-      IF CompileAll(modules, graph, exename) THEN
-        tempWindowed := needWindowed & T.IsFS();
-        IF tempWindowed THEN T.SwitchToWindow END;
-        RunProgram(exename)
+      modules := UsedModuleList(modname, mainFname, ok,
+        errFname, errLine, errCol);
+      IF ok THEN
+        graph := ImportsGraph(modules);
+        needWindowed := graph;
+        IF CompileAll(modules, graph, exename) THEN
+          tempWindowed := needWindowed & T.IsFS();
+          IF tempWindowed THEN T.SwitchToWindow END;
+          RunProgram(exename)
+        END
+      ELSE
+        FocusOrOpenFile(errFname);
+        e := app.windows(Editor.Editor);
+        e.text.MoveToLineCol(errLine, errCol, e.h - 2);
+        FoStrings.MakeErrorStr(401(*file contains wrong module name*), s);
+        ShowErrors(s)
       END
     END
   END
@@ -1150,6 +1186,7 @@ BEGIN
   ParseArgs(fs, sw, w, h, fnames);
   T.Settings(106, 25, {T.resizable(*, T.window*)});
   (*T.Settings(240, 61, {T.resizable, T.window});*)
+  FoStrings.SetLang('en');
   T.SetTitle('Free Oberon');
   T.Init;
   IF T.Done THEN

src/Texts.Mod

@@ -22,13 +22,13 @@ TYPE
 
   Scanner* = RECORD(Reader)
     nextCh*: CHAR;
+    c*: CHAR;
     line*, class*: INTEGER;
     i*: INTEGER;
     x*: REAL;
     (*y*: LONGREAL;*)
-    c*: CHAR;
     len*: LONGINT;
-    s*: ARRAY 512 OF CHAR
+    s*: ARRAY 1900 OF CHAR
   END;
 
 PROCEDURE Open*(T: Text; fname: ARRAY OF CHAR);
@@ -39,9 +39,9 @@ BEGIN T.F := Files.Old(fname);
   END
 END Open;
 
-PROCEDURE Next*(VAR S: Scanner);
+PROCEDURE Read*(VAR R: Reader; VAR ch: CHAR);
 BEGIN
-  Files.ReadChar(S.rider, S.nextCh)
+  Files.ReadChar(R.rider, S.nextCh)
 END Next;
 
 PROCEDURE OpenScanner*(VAR S: Scanner; T: Text; pos: LONGINT);

src/Texts0.Mod

@@ -0,0 +1,938 @@
+MODULE Texts;  (** CAS/HM 23.9.93 -- interface based on Texts by JG/NW 6.12.91**)  (* << RC, MB, JT *)
+  IMPORT
+    s := SYSTEM, Files, Modules, Reals;
+
+  TYPE
+    SHORTINT = s.INT8; INTEGER = s.INT16; LONGINT = s.INT32; HUGEINT = s.INT64;
+    CHAR = s.CHAR8; LONGCHAR = s.CHAR16; REAL = s.REAL32; LONGREAL = s.REAL64;
+
+  (*--- insert field e: Elem into Texts.Scanner and change Texts.Scan to set it in case of class=6 *)
+
+
+  CONST
+    Displaywhite = 15;
+    ElemChar* = 1CX;
+    TAB = 9X; CR = 0DX; maxD = 9;
+    (**FileMsg.id**)
+      load* = 0; store* = 1;
+    (**Notifier op**)
+      replace* = 0; insert* = 1; delete* = 2; unmark* = 3;
+    (**Scanner.class**)
+      Inval* = 0; Name* = 1; String* = 2; Int* = 3; Real* = 4; LongReal* = 5; Char* = 6;
+
+    textTag = 0F0X; DocBlockId = 0F7X; version = 01X;
+
+  TYPE
+    FontsFont = POINTER TO FontDesc;
+    FontDesc = RECORD
+      name: ARRAY 32 OF CHAR;
+    END ;
+
+    Run = POINTER TO RunDesc;
+    RunDesc = EXTENSIBLE RECORD
+      prev, next: Run;
+      len: LONGINT;
+      fnt: FontsFont;
+      col, voff: SHORTINT;
+      ascii: BOOLEAN  (* << *)
+    END;
+
+    Piece = POINTER TO PieceDesc;
+    PieceDesc = RECORD (RunDesc)
+      file: Files.File;
+      org: LONGINT
+    END;
+
+    Elem* = POINTER TO ElemDesc;
+    Buffer* = POINTER TO BufDesc;
+    Text* = POINTER TO TextDesc;
+
+    ElemMsg* = EXTENSIBLE RECORD END;
+    Handler* = PROCEDURE (e: Elem; VAR msg: ElemMsg);
+
+    ElemDesc* = EXTENSIBLE RECORD (RunDesc)
+      W*, H*: LONGINT;
+      handle*: Handler;
+      base: Text
+    END;
+
+    FileMsg* = RECORD (ElemMsg)
+      id*: INTEGER;
+      pos*: LONGINT;
+      r*: Files.Rider
+    END;
+
+    CopyMsg* = RECORD (ElemMsg)
+      e*: Elem
+    END;
+
+    IdentifyMsg* = RECORD (ElemMsg)
+      mod*, proc*: ARRAY 32 OF CHAR
+    END;
+
+
+    BufDesc* = RECORD
+      len*: LONGINT;
+      head: Run
+    END;
+
+    Notifier* = PROCEDURE (T: Text; op: INTEGER; beg, end: LONGINT);
+    TextDesc* = RECORD
+      len*: LONGINT;
+      notify*: Notifier;
+      head, cache: Run;
+      corg: LONGINT
+    END;
+
+    Reader* = EXTENSIBLE RECORD
+      eot*: BOOLEAN;
+      fnt*: FontsFont;
+      col*, voff*: SHORTINT;
+      elem*: Elem;
+      rider: Files.Rider;
+      run: Run;
+      org, off: LONGINT
+    END;
+
+    Scanner* = RECORD (Reader)
+      nextCh*: CHAR;
+      line*, class*: INTEGER;
+      i*: LONGINT;
+      x*: REAL;
+      y*: LONGREAL;
+      c*: CHAR;
+      len*: SHORTINT;
+      s*: ARRAY 64 OF CHAR  (* << *)
+    END;
+
+    Writer* = RECORD
+      buf*: Buffer;
+      fnt*: FontsFont;
+      col*, voff*: SHORTINT;
+      rider: Files.Rider;
+      file: Files.File
+    END;
+
+    Alien = POINTER TO RECORD (ElemDesc)
+      file: Files.File;
+      org, span: LONGINT;
+      mod, proc: ARRAY 32 OF CHAR
+    END;
+
+  VAR
+    new*: Elem;
+    del: Buffer;
+    FontsDefault: FontsFont;
+
+
+  PROCEDURE FontsThis(VAR name: ARRAY OF CHAR): FontsFont;
+    VAR F: FontsFont;
+  BEGIN
+    NEW(F); F.name := name$; RETURN F
+  END FontsThis;
+
+  (* run primitives *)
+
+  PROCEDURE Find (T: Text; VAR pos: LONGINT; VAR u: Run; VAR org, off: LONGINT);
+    VAR v: Run; m: LONGINT;
+  BEGIN
+    IF pos >= T.len THEN pos := T.len; u := T.head; org := T.len; off := 0; T.cache := T.head; T.corg := 0
+    ELSE v := T.cache.next; m := pos - T.corg;
+      IF pos >= T.corg THEN
+        WHILE m >= v.len DO DEC(m, v.len); v := v.next END
+      ELSE
+        WHILE m < 0 DO v := v.prev; INC(m, v.len) END;
+      END;
+      u := v; org := pos - m; off := m; T.cache := v.prev; T.corg := org
+    END
+  END Find;
+
+  PROCEDURE Split (off: LONGINT; VAR u, un: Run);
+    VAR p, U: Piece;
+  BEGIN
+    IF off = 0 THEN un := u; u := un.prev
+    ELSIF off >= u.len THEN un := u.next
+    ELSE NEW(p); un := p; U := u(Piece);
+      p^ := U^; INC(p.org, off); DEC(p.len, off); DEC(U.len, p.len);
+      p.ascii := u.ascii; p.prev := U; p.next := U.next; p.next.prev := p; U.next := p  (* << *)
+    END
+  END Split;
+
+  PROCEDURE Merge (T: Text; u: Run; VAR v: Run);
+    VAR p, q: Piece;
+  BEGIN
+    IF (u IS Piece) & (v IS Piece) & (u.fnt.name = v.fnt.name) & (u.col = v.col) & (u.voff = v.voff)
+    & (u(Piece).ascii = v(Piece).ascii) THEN  (* << *)
+      p := u(Piece); q := v(Piece);
+      IF (p.file = q.file) & (p.org + p.len = q.org) THEN
+        IF T.cache = u THEN INC(T.corg, q.len)
+        ELSIF T.cache = v THEN T.cache := T.head; T.corg := 0
+        END;
+        INC(p.len, q.len); v := v.next
+      END
+    END
+  END Merge;
+
+  PROCEDURE Splice (un, v, w: Run; base: Text);  (* (u, un) -> (u, v, w, un) *)
+    VAR u: Run;
+  BEGIN
+    IF v # w.next THEN u := un.prev;
+      u.next := v; v.prev := u; un.prev := w; w.next := un;
+      REPEAT
+        IF v IS Elem THEN v(Elem).base := base END;
+        v := v.next
+      UNTIL v = un
+    END
+  END Splice;
+
+  PROCEDURE ClonePiece (p: Piece): Piece;
+    VAR q: Piece;
+  BEGIN NEW(q); q^ := p^; RETURN q
+  END ClonePiece;
+
+  PROCEDURE CloneElem (e: Elem): Elem;
+    VAR msg: CopyMsg;
+  BEGIN msg.e := NIL; e.handle(e, msg); RETURN msg.e
+  END CloneElem;
+
+
+  (** Elements **)
+
+  PROCEDURE CopyElem* (SE, DE: Elem);
+  BEGIN DE.len := SE.len; DE.fnt := SE.fnt; DE.col := SE.col; DE.voff := SE.voff;
+    DE.W := SE.W; DE.H := SE.H; DE.handle := SE.handle
+  END CopyElem;
+
+  PROCEDURE ElemBase* (E: Elem): Text;
+  BEGIN RETURN E.base
+  END ElemBase;
+
+  PROCEDURE ElemPos* (E: Elem): LONGINT;
+    VAR u: Run; pos: LONGINT;
+  BEGIN u := E.base.head.next; pos := 0;
+    WHILE u # E DO pos := pos + u.len; u := u.next END;
+    RETURN pos
+  END ElemPos;
+
+
+  PROCEDURE HandleAlien (E: Elem; VAR msg: ElemMsg);
+    VAR e: Alien; r: Files.Rider; i: LONGINT; ch: CHAR;
+  BEGIN
+    WITH E: Alien DO
+      IF msg IS CopyMsg THEN
+        WITH msg: CopyMsg DO NEW(e); CopyElem(E, e);
+          e.file := E.file; e.org := E.org; e.span := E.span; e.mod := E.mod; e.proc := E.proc;
+          msg.e := e
+        END
+      ELSIF msg IS IdentifyMsg THEN
+        WITH msg: IdentifyMsg DO
+          msg.mod := E.mod$; msg.proc := E.proc$; msg.mod[31] := 1X (*alien*)
+        END
+      ELSIF msg IS FileMsg THEN
+        WITH msg: FileMsg DO
+          IF msg.id = store THEN Files.Set(r, E.file, E.org); i := E.span;
+            WHILE i > 0 DO Files.ReadChar(r, ch); Files.WriteChar(msg.r, ch); DEC(i) END
+          END
+        END
+      END
+    END
+  END HandleAlien;
+
+
+  (** Buffers **)
+
+  PROCEDURE OpenBuf* (B: Buffer);
+    VAR u: Run;
+  BEGIN NEW(u); u.next := u; u.prev := u; B.head := u; B.len := 0
+  END OpenBuf;
+
+  PROCEDURE Copy* (SB, DB: Buffer);
+    VAR u, v, vn: Run;
+  BEGIN u := SB.head.next; v := DB.head.prev;
+    WHILE u # SB.head DO
+      IF u IS Piece THEN vn := ClonePiece(u(Piece)) ELSE vn := CloneElem(u(Elem)) END;
+      v.next := vn; vn.prev := v; v := vn; u := u.next
+    END;
+    v.next := DB.head; DB.head.prev := v;
+    INC(DB.len, SB.len)
+  END Copy;
+
+  PROCEDURE Recall* (VAR B: Buffer);
+  BEGIN B := del; del := NIL
+  END Recall;
+
+
+  (** Texts **)
+
+  PROCEDURE Save* (T: Text; beg, end: LONGINT; B: Buffer);
+    VAR u, v, w, wn: Run; uo, ud, vo, vd: LONGINT;
+  BEGIN Find(T, beg, u, uo, ud); Find(T, end, v, vo, vd);
+    w := B.head.prev;
+    WHILE u # v DO
+      IF u IS Piece THEN wn := ClonePiece(u(Piece)); DEC(wn.len, ud); INC(wn(Piece).org, ud)
+      ELSE wn := CloneElem(u(Elem))
+      END;
+      w.next := wn; wn.prev := w; w := wn; u := u.next; ud := 0
+    END;
+    IF vd > 0 THEN (*v IS Piece*) wn := ClonePiece(v(Piece)); wn.len := vd - ud; INC(wn(Piece).org, ud);
+      w.next := wn; wn.prev := w; w := wn
+    END;
+    w.next := B.head; B.head.prev := w;
+    INC(B.len, end - beg)
+  END Save;
+
+  PROCEDURE Insert* (T: Text; pos: LONGINT; B: Buffer);
+    VAR u, un, v: Run; p, q: Piece; uo, ud, len: LONGINT;
+  BEGIN Find(T, pos, u, uo, ud); Split(ud, u, un);
+    len := B.len; v := B.head.next;
+    Merge(T, u, v); Splice(un, v, B.head.prev, T);
+    INC(T.len, len); B.head.next := B.head; B.head.prev := B.head; B.len := 0;
+    IF T.notify # NIL THEN T.notify(T, insert, pos, pos+len) END
+  END Insert;
+
+  PROCEDURE Append* (T: Text; B: Buffer);
+    VAR v: Run; pos, len: LONGINT;
+  BEGIN pos := T.len; len := B.len; v := B.head.next;
+    Merge(T, T.head.prev, v); Splice(T.head, v, B.head.prev, T);
+    INC(T.len, len); B.head.next := B.head; B.head.prev := B.head; B.len := 0;
+    IF T.notify # NIL THEN T.notify(T, insert, pos, pos+len) END
+  END Append;
+
+  PROCEDURE Delete* (T: Text; beg, end: LONGINT);
+    VAR c, u, un, v, vn: Run; co, uo, ud, vo, vd: LONGINT;
+  BEGIN
+    Find(T, beg, u, uo, ud); Split(ud, u, un); c := T.cache; co := T.corg;
+    Find(T, end, v, vo, vd); Split(vd, v, vn); T.cache := c; T.corg := co;
+    NEW(del); OpenBuf(del); del.len := end - beg;
+    Splice(del.head, un, v, NIL);
+    Merge(T, u, vn); u.next := vn; vn.prev := u;
+    DEC(T.len, end - beg);
+    IF T.notify # NIL THEN T.notify(T, delete, beg, end) END
+  END Delete;
+
+  PROCEDURE ChangeLooks* (T: Text; beg, end: LONGINT; sel: SET; fnt: FontsFont; col, voff: SHORTINT);
+    VAR c, u, un, v, vn: Run; co, uo, ud, vo, vd: LONGINT;
+  BEGIN Find(T, beg, u, uo, ud); Split(ud, u, un); c := T.cache; co := T.corg;
+    Find(T, end, v, vo, vd); Split(vd, v, vn); T.cache := c; T.corg := co;
+    WHILE un # vn DO
+      IF (0 IN sel) & (fnt # NIL) THEN un.fnt := fnt END;
+      IF 1 IN sel THEN un.col := col END;
+      IF 2 IN sel THEN un.voff := voff END;
+      Merge(T, u, un);
+      IF u.next = un THEN u := un; un := un.next ELSE u.next := un; un.prev := u END
+    END;
+    Merge(T, u, un); u.next := un; un.prev := u;
+    IF T.notify # NIL THEN T.notify(T, replace, beg, end) END
+  END ChangeLooks;
+
+
+  (** Readers **)
+
+  PROCEDURE OpenReader* (VAR R: Reader; T: Text; pos: LONGINT);
+    VAR u: Run;
+  BEGIN
+    IF pos >= T.len THEN pos := T.len ELSIF pos < 0 THEN pos := 0 END;
+    Find(T, pos, u, R.org, R.off); R.run := u; R.eot := FALSE;
+    IF u IS Piece THEN
+      Files.Set(R.rider, u(Piece).file, u(Piece).org + R.off)
+    END
+  END OpenReader;
+
+  PROCEDURE Read* (VAR R: Reader; OUT ch: CHAR);
+    VAR u: Run; pos: LONGINT; nextch: CHAR;
+  BEGIN u := R.run; R.fnt := u.fnt; R.col := u.col; R.voff := u.voff; INC(R.off);
+    IF u IS Piece THEN Files.ReadChar(R.rider, ch); R.elem := NIL;
+      IF (ch = 0AX) & u(Piece).ascii THEN ch := CR (* << LF to CR *)
+      ELSIF (ch = CR) & u(Piece).ascii THEN (* << CR LF to CR *)
+         pos := SHORT(Files.Pos(R.rider)); Files.ReadChar(R.rider, nextch);
+         IF nextch = 0AX THEN INC(R.off) ELSE Files.Set(R.rider, u(Piece).file, pos) END
+      END
+    ELSIF u IS Elem THEN ch := ElemChar; R.elem := u(Elem)
+    ELSE ch := 0X; R.elem := NIL; R.eot := TRUE
+    END;
+    IF R.off = u.len THEN INC(R.org, u.len); u := u.next;
+      IF u IS Piece THEN
+        WITH u: Piece DO Files.Set(R.rider, u.file, u.org) END
+      END;
+      R.run := u; R.off := 0
+    END
+  END Read;
+
+  PROCEDURE ReadLong* (VAR R: Reader; OUT longch: LONGCHAR): BOOLEAN;
+    VAR ch: CHAR; val: LONGINT;
+  BEGIN Read(R, ch);
+    IF ch < 80X THEN
+      longch := ch
+    ELSIF ch < 0E0X THEN
+      val := ORD(ch) - 192;
+      IF val < 0 THEN RETURN FALSE END;
+      Read(R, ch); val := val * 64 + ORD(ch) - 128;
+      IF (ch < 80X) OR (ch >= 0E0X) THEN RETURN FALSE END;
+      longch := CHR(val)
+    ELSIF ch < 0F0X THEN 
+      val := ORD(ch) - 224;
+      Read(R, ch); val := val * 64 + ORD(ch) - 128;
+      IF (ch < 80X) OR (ch >= 0E0X) THEN RETURN FALSE END;
+      Read(R, ch); val := val * 64 + ORD(ch) - 128;
+      IF (ch < 80X) OR (ch >= 0E0X) THEN RETURN FALSE END;
+      longch := CHR(val)
+    ELSE
+      RETURN FALSE
+    END;
+    RETURN TRUE
+  END ReadLong;
+
+  PROCEDURE ReadElem* (VAR R: Reader);
+    VAR u, un: Run;
+  BEGIN u := R.run;
+    WHILE u IS Piece DO INC(R.org, u.len); u := u.next END;
+    IF u IS Elem THEN un := u.next; R.run := un; INC(R.org); R.off := 0;
+      R.fnt := u.fnt; R.col := u.col; R.voff := u.voff; R.elem := u(Elem);
+      IF un IS Piece THEN
+        WITH un: Piece DO Files.Set(R.rider, un.file, un.org) END
+      END
+    ELSE R.eot := TRUE; R.elem := NIL
+    END
+  END ReadElem;
+
+  PROCEDURE ReadPrevElem* (VAR R: Reader);
+    VAR u: Run;
+  BEGIN u := R.run.prev;
+    WHILE u IS Piece DO DEC(R.org, u.len); u := u.prev END;
+    IF u IS Elem THEN R.run := u; DEC(R.org); R.off := 0;
+      R.fnt := u.fnt; R.col := u.col; R.voff := u.voff; R.elem := u(Elem)
+    ELSE R.eot := TRUE; R.elem := NIL
+    END
+  END ReadPrevElem;
+
+  PROCEDURE Pos* (VAR R: Reader): LONGINT;
+  BEGIN RETURN R.org + R.off
+  END Pos;
+
+
+  (** Scanners --------------- NW --------------- **)
+
+  PROCEDURE OpenScanner* (VAR S: Scanner; T: Text; pos: LONGINT);
+  BEGIN OpenReader(S, T, pos); S.line := 0; S.nextCh := " "
+  END OpenScanner;
+
+  (*IEEE floating point formats:
+    x = 2^(e-127) * 1.m    bit 0: sign, bits 1- 8: e, bits  9-31: m
+    x = 2^(e-1023) * 1.m   bit 0: sign, bits 1-11: e, bits 12-63: m *)
+
+  PROCEDURE Scan* (VAR S: Scanner);
+    CONST maxD = 32;
+    VAR ch, term: CHAR;
+      neg, negE, hex: BOOLEAN;
+      i, j, h: SHORTINT;
+      e: INTEGER; k: LONGINT;
+      x, f: REAL; y, g: LONGREAL;
+      d: ARRAY maxD OF CHAR;
+
+    PROCEDURE ReadScaleFactor;
+    BEGIN Read(S, ch);
+      IF ch = "-" THEN negE := TRUE; Read(S, ch)
+      ELSE negE := FALSE;
+        IF ch = "+" THEN Read(S, ch) END
+      END;
+      WHILE ("0" <= ch) & (ch <= "9") DO
+        e := SHORT(e*10 + ORD(ch) - 30H); Read(S, ch)
+      END
+    END ReadScaleFactor;
+
+  BEGIN ch := S.nextCh; i := 0;
+    LOOP
+      IF ch = CR THEN INC(S.line)
+      ELSIF (ch # " ") & (ch # TAB) THEN EXIT
+      END ;
+      Read(S, ch)
+    END;
+    IF ("A" <= CAP(ch)) & (CAP(ch) <= "Z") OR (ch = "/") OR (ch = ".") THEN (*name*)  (* << *)
+      REPEAT S.s[i] := ch; INC(i); Read(S, ch)
+      UNTIL (CAP(ch) > "Z") & (ch # "_")  (* << *)
+        OR ("A" > CAP(ch)) & (ch > "9")
+        OR ("0" > ch) & (ch # ".") & (ch # "/")  (* << *)
+        OR (i = 63);  (* << *)
+      S.s[i] := 0X; S.len := i; S.class := 1
+    ELSIF ch = 22X THEN (*literal string*)
+      Read(S, ch);
+      WHILE (ch # 22X) & (ch >= " ") & (i # 63) DO  (* << *)
+        S.s[i] := ch; INC(i); Read(S, ch)
+      END;
+      S.s[i] := 0X; S.len := SHORT(SHORT(i+1)); Read(S, ch); S.class := 2
+    ELSE
+      IF ch = "-" THEN neg := TRUE; Read(S, ch) ELSE neg := FALSE END ;
+      IF ("0" <= ch) & (ch <= "9") THEN (*number*)
+        hex := FALSE; j := 0;
+        LOOP d[i] := ch; INC(i); Read(S, ch);
+          IF ch < "0" THEN EXIT END;
+          IF "9" < ch THEN
+            IF ("A" <= ch) & (ch <= "F") THEN hex := TRUE; ch := SHORT(CHR(ORD(ch)-7))
+            ELSIF ("a" <= ch) & (ch <= "f") THEN hex := TRUE; ch := SHORT(CHR(ORD(ch)-27H))
+            ELSE EXIT
+            END
+          END
+        END;
+        IF ch = "H" THEN (*hex number*)
+          Read(S, ch); S.class := 3;
+          IF i-j > 8 THEN j := SHORT(SHORT(i-8)) END;
+          k := ORD(d[j]) - 30H; INC(j);
+          IF (i-j = 7) & (k >= 8) THEN DEC(k, 16) END ;
+          WHILE j < i DO k := k*10H + (ORD(d[j]) - 30H); INC(j) END ;
+          IF neg THEN S.i := -k ELSE S.i := k END
+        ELSIF ch = "." THEN (*read real*)
+          Read(S, ch); h := i;
+          WHILE ("0" <= ch) & (ch <= "9") DO d[i] := ch; INC(i); Read(S, ch) END ;
+          IF ch = "D" THEN
+            e := 0; y := 0; g := 1;
+            REPEAT y := y*10 + (ORD(d[j]) - 30H); INC(j) UNTIL j = h;
+            WHILE j < i DO g := g/10; y := (ORD(d[j]) - 30H)*g + y; INC(j) END ;
+            ReadScaleFactor;
+            IF negE THEN
+              IF e <= 308 THEN y := y / Reals.TenL(e) ELSE y := 0 END
+            ELSIF e > 0 THEN
+              IF e <= 308 THEN y := Reals.TenL(e) * y ELSE HALT(40) END
+            END ;
+            IF neg THEN y := -y END ;
+            S.class := 5; S.y := y
+          ELSE e := 0; x := 0; f := 1;
+            REPEAT x := x*10 + (ORD(d[j]) - 30H); INC(j) UNTIL j = h;
+            WHILE j < i DO f := f/10; x := (ORD(d[j])-30H)*f + x; INC(j) END;
+            IF ch = "E" THEN ReadScaleFactor END ;
+            IF negE THEN
+              IF e <= 38 THEN x := x / Reals.Ten(e) ELSE x := 0 END
+            ELSIF e > 0 THEN
+              IF e <= 38 THEN x := Reals.Ten(e) * x ELSE HALT(40) END
+            END ;
+            IF neg THEN x := -x END ;
+            S.class := 4; S.x := x
+          END ;
+          IF hex THEN S.class := 0 END
+        ELSE (*decimal integer*)
+          S.class := 3; k := 0;
+          REPEAT k := k*10 + (ORD(d[j]) - 30H); INC(j) UNTIL j = i;
+          IF neg THEN S.i := -k ELSE S.i := k END;
+          IF hex THEN S.class := 0 ELSE S.class := 3 END
+        END
+      ELSE S.class := 6;
+        IF neg THEN S.c := "-" ELSE S.c := ch; Read(S, ch) END
+      END
+    END;
+    S.nextCh := ch
+  END Scan;
+
+
+  (** Writers **)
+
+  PROCEDURE OpenWriter* (VAR W: Writer);
+  BEGIN NEW(W.buf); OpenBuf(W.buf);
+    W.fnt := FontsDefault; W.col := Displaywhite; W.voff := 0;
+    W.file := Files.New(""); Files.Set(W.rider, W.file, 0)
+  END OpenWriter;
+
+  PROCEDURE SetFont* (VAR W: Writer; fnt: FontsFont);
+  BEGIN W.fnt := fnt
+  END SetFont;
+
+  PROCEDURE SetColor* (VAR W: Writer; col: SHORTINT);
+  BEGIN W.col := col
+  END SetColor;
+
+  PROCEDURE SetOffset* (VAR W: Writer; voff: SHORTINT);
+  BEGIN W.voff := voff
+  END SetOffset;
+
+
+  PROCEDURE Write* (VAR W: Writer; ch: CHAR);
+    VAR u, un: Run; p: Piece;
+  BEGIN Files.WriteChar(W.rider, ch); INC(W.buf.len); un := W.buf.head; u := un.prev;
+    IF (u IS Piece) & (u(Piece).file = W.file) & (u.fnt.name = W.fnt.name) & (u.col = W.col) & (u.voff = W.voff)
+    & ~u(Piece).ascii THEN (* << *)
+      INC(u.len)
+    ELSE NEW(p); u.next := p; p.prev := u; p.next := un; un.prev := p;
+      p.len := 1; p.fnt := W.fnt; p.col := W.col; p.voff := W.voff;
+      p.file := W.file; p.org := SHORT(Files.Length(W.file)) - 1; p.ascii := FALSE (* << *)
+    END
+  END Write;
+
+  PROCEDURE WriteElem* (VAR W: Writer; e: Elem);
+    VAR u, un: Run;
+  BEGIN
+    IF e.base # NIL THEN HALT(99) END;
+    INC(W.buf.len); e.len := 1; e.fnt := W.fnt; e.col := W.col; e.voff := W.voff;
+    un := W.buf.head; u := un.prev; u.next := e; e.prev := u; e.next := un; un.prev := e
+  END WriteElem;
+
+  PROCEDURE WriteLn* (VAR W: Writer);
+  BEGIN Write(W, CR)
+  END WriteLn;
+
+  PROCEDURE WriteString* (VAR W: Writer; IN s: ARRAY OF CHAR);
+    VAR i: INTEGER;
+  BEGIN i := 0;
+    WHILE s[i] >= " " DO Write(W, s[i]); INC(i) END
+  END WriteString;
+
+  PROCEDURE WriteInt* (VAR W: Writer; x, n: LONGINT);
+  VAR
+    i: INTEGER; x0: LONGINT;
+    a: ARRAY 22 OF CHAR;
+  BEGIN i := 0;
+    IF x < 0 THEN
+      IF x = MIN(LONGINT) THEN
+        IF SIZE(LONGINT) = 4 THEN
+          WriteString(W, " -2147483648")
+        ELSE
+          WriteString(W, " -9223372036854775808")
+        END;
+        RETURN
+      ELSE DEC(n); x0 := -x
+      END
+    ELSE x0 := x
+    END;
+    REPEAT
+      a[i] := SHORT(CHR(x0 MOD 10 + 30H)); x0 := x0 DIV 10; INC(i)
+    UNTIL x0 = 0;
+    WHILE n > i DO Write(W, " "); DEC(n) END;
+    IF x < 0 THEN Write(W, "-") END;
+    REPEAT DEC(i); Write(W, a[i]) UNTIL i = 0
+  END WriteInt;
+
+  PROCEDURE WriteLongInt* (VAR W: Writer; x: HUGEINT; n: LONGINT);
+  VAR
+    i: LONGINT; x0: HUGEINT;
+    a: ARRAY 22 OF CHAR;
+  BEGIN i := 0;
+    IF x < 0 THEN
+      IF x = MIN(HUGEINT) THEN
+        IF SIZE(HUGEINT) = 4 THEN
+          WriteString(W, " -2147483648")
+        ELSE
+          WriteString(W, " -9223372036854775808")
+        END;
+        RETURN
+      ELSE DEC(n); x0 := -x
+      END
+    ELSE x0 := x
+    END;
+    REPEAT
+      a[i] := SHORT(CHR(x0 MOD 10 + 30H)); x0 := x0 DIV 10; INC(i)
+    UNTIL x0 = 0;
+    WHILE n > i DO Write(W, " "); DEC(n) END;
+    IF x < 0 THEN Write(W, "-") END;
+    REPEAT DEC(i); Write(W, a[i]) UNTIL i = 0
+  END WriteLongInt;
+
+  PROCEDURE WriteHex* (VAR W: Writer; x: LONGINT);
+    VAR i: INTEGER; y: LONGINT;
+      a: ARRAY 8 OF CHAR;
+  BEGIN i := 0; Write(W, " ");
+    REPEAT y := x MOD 10H;
+      IF y < 10 THEN a[i] := SHORT(CHR(y + 30H)) ELSE a[i] := SHORT(CHR(y + 37H)) END;
+      x := x DIV 10H; INC(i)
+    UNTIL i = 8;
+    REPEAT DEC(i); Write(W, a[i]) UNTIL i = 0
+  END WriteHex;
+
+  PROCEDURE WriteLongHex* (VAR W: Writer; x: HUGEINT);
+    VAR i: INTEGER; y: LONGINT;
+      a: ARRAY 16 OF CHAR;
+  BEGIN i := 0; Write(W, " ");
+    REPEAT y := SHORT(x) MOD 10H;
+      IF y < 10 THEN a[i] := SHORT(CHR(y + 30H)) ELSE a[i] := SHORT(CHR(y + 37H)) END;
+      x := x DIV 10H; INC(i)
+    UNTIL i = 16;
+    REPEAT DEC(i); Write(W, a[i]) UNTIL i = 0
+  END WriteLongHex;
+
+  PROCEDURE WriteReal* (VAR W: Writer; x: REAL; n: INTEGER);
+    VAR e: INTEGER; x0: REAL;
+      d: ARRAY maxD OF CHAR;
+  BEGIN e := Reals.Expo(x);
+    IF e = 0 THEN
+      WriteString(W, "0.0");
+      REPEAT DEC(n) UNTIL n <= 3
+    ELSIF e = 255 THEN
+      WriteString(W, "NaN");
+    ELSE
+      IF n <= 9 THEN n := 3 ELSE DEC(n, 6) END;
+      REPEAT DEC(n) UNTIL n <= 8;
+      (*there are 2 < n <= 8 digits to be written*)
+      IF x < 0.0 THEN Write(W, "-"); x := -x END;
+      e := SHORT((e - 127) * 77 DIV 256);
+      IF e >= 0 THEN x := x / Reals.Ten(e) ELSE x := Reals.Ten(SHORT(-e)) * x END;
+      IF x >= 10.0 THEN x := 0.1*x; INC(e) END;
+      x0 := Reals.Ten(SHORT(n-1)); x := x0*x + 0.5;
+      IF x >= 10.0*x0 THEN x := x*0.1; INC(e) END;
+      Reals.Convert(x, n, d);
+      DEC(n); Write(W, d[n]); Write(W, ".");
+      REPEAT DEC(n); Write(W, d[n]) UNTIL n = 0;
+      Write(W, "E");
+      IF e >= 0 THEN Write(W, "+") END;
+      WriteInt(W, e, 0)
+    END
+  END WriteReal;
+
+  PROCEDURE WriteRealFix* (VAR W: Writer; x: REAL; n, k: INTEGER);
+    VAR e, i: INTEGER; sign: CHAR; x0: REAL;
+      d: ARRAY maxD OF CHAR;
+
+    PROCEDURE seq(ch: CHAR; n: INTEGER);
+    BEGIN WHILE n > 0 DO Write(W, ch); DEC(n) END
+    END seq;
+
+    PROCEDURE dig(n: INTEGER);
+    BEGIN
+      WHILE n > 0 DO
+        DEC(i); Write(W, d[i]); DEC(n)
+      END
+    END dig;
+
+  BEGIN e := Reals.Expo(x);
+    IF k < 0 THEN k := 0 END;
+    IF e = 0 THEN seq(" ", SHORT(n-k-2)); Write(W, "0"); seq(" ", SHORT(k+1))
+    ELSIF e = 255 THEN WriteString(W, " NaN"); seq(" ", SHORT(n-4))
+    ELSE e := SHORT((e - 127) * 77 DIV 256);
+      IF x < 0 THEN sign := "-"; x := -x ELSE sign := " " END;
+      IF e >= 0 THEN  (*x >= 1.0,  77/256 = log 2*) x := x/Reals.Ten(e)
+        ELSE (*x < 1.0*) x := Reals.Ten(SHORT(-e)) * x
+      END;
+      IF x >= 10.0 THEN x := 0.1*x; INC(e) END;
+      (* 1 <= x < 10 *)
+      IF k+e >= maxD-1 THEN k := SHORT(maxD-1-e)
+        ELSIF k+e < 0 THEN k := SHORT(-e); x := 0.0
+      END;
+      x0 := Reals.Ten(SHORT(k+e)); x := x0*x + 0.5;
+      IF x >= 10.0*x0 THEN INC(e) END;
+      (*e = no. of digits before decimal point*)
+      INC(e); i := SHORT(k+e); Reals.Convert(x, i, d);
+      IF e > 0 THEN
+        seq(" ", SHORT(n-e-k-2)); Write(W, sign); dig(e);
+        Write(W, "."); dig(k)
+      ELSE seq(" ", SHORT(n-k-3));
+        Write(W, sign); Write(W, "0"); Write(W, ".");
+        seq("0", SHORT(-e)); dig(SHORT(k+e))
+      END
+    END
+  END WriteRealFix;
+
+  PROCEDURE WriteRealHex* (VAR W: Writer; x: REAL);
+    VAR i: INTEGER;
+      d: ARRAY 8 OF CHAR;
+  BEGIN Reals.ConvertH(x, d); i := 0;
+    REPEAT Write(W, d[i]); INC(i) UNTIL i = 8
+  END WriteRealHex;
+
+  PROCEDURE WriteLongReal* (VAR W: Writer; x: LONGREAL; n: INTEGER);
+    VAR ch: CHAR; i: INTEGER; dotzero: BOOLEAN;
+      d: ARRAY 28 OF CHAR;
+  BEGIN
+    Reals.RealToStr(x, n, d);
+    i := 0; ch := d[0]; dotzero := TRUE;
+    WHILE (ch # 0X) & (ch # "E") DO
+      IF (ch = ".") OR (ch > "9") THEN dotzero := FALSE END; (* NaN, -INF/+INF *)
+      Write(W, ch); INC(i); ch := d[i]
+    END;
+    IF ch = "E" THEN
+      Write(W, "E"); INC(i); ch := d[i];
+      IF (ch = "+") OR (ch = "-") THEN Write(W, ch); INC(i); ch := d[i] END;
+      IF ch = "0" THEN INC(i); ch := d[i];
+        IF ch = "0" THEN INC(i); ch := d[i] END
+      END;
+      WHILE ch # 0X DO Write(W, ch); INC(i); ch := d[i] END
+    ELSIF dotzero THEN
+      Write(W, "."); Write(W, "0")
+    END
+  END WriteLongReal;
+
+  PROCEDURE WriteLongRealHex* (VAR W: Writer; x: LONGREAL);
+    VAR i: INTEGER;
+      d: ARRAY 16 OF CHAR;
+  BEGIN Reals.ConvertHL(x, d); i := 0;
+    REPEAT Write(W, d[i]); INC(i) UNTIL i = 16
+  END WriteLongRealHex;
+
+  PROCEDURE WriteDate* (VAR W: Writer; t, d: LONGINT);
+
+    PROCEDURE WritePair(ch: CHAR; x: LONGINT);
+    BEGIN Write(W, ch);
+      Write(W, SHORT(CHR(x DIV 10 + 30H))); Write(W, SHORT(CHR(x MOD 10 + 30H)))
+    END WritePair;
+
+  BEGIN
+    WritePair(" ", d MOD 32); WritePair(".", d DIV 32 MOD 16); WritePair(".", d DIV 512 MOD 128);
+    WritePair(" ", t DIV 4096 MOD 32); WritePair(":", t DIV 64 MOD 64); WritePair(":", t MOD 64)
+  END WriteDate;
+
+
+  (** Text Filing **)
+
+  PROCEDURE Load0 (VAR r: Files.Rider; T: Text);
+    VAR u, un: Run; p: Piece; e: Elem;
+      org, pos, hlen, plen: LONGINT; ecnt, fno, fcnt, col, voff: SHORTINT;
+      f: Files.File;
+      msg: FileMsg;
+      mods, procs: ARRAY 64, 32 OF CHAR;
+      name: ARRAY 32 OF CHAR;
+      fnts: ARRAY 32 OF FontsFont;
+
+    PROCEDURE LoadElem (VAR r: Files.Rider; pos, span: LONGINT; VAR e: Elem);
+      VAR M: Modules.Module; Cmd: Modules.Command; a: Alien;
+        org, ew, eh: LONGINT; eno: SHORTINT;
+    BEGIN new := NIL;
+      Files.ReadInt(r, ew); Files.ReadInt(r, eh); Files.ReadByte(r, eno);
+      IF eno > ecnt THEN ecnt := eno; Files.ReadString(r, mods[eno]); Files.ReadString(r, procs[eno]) END;
+      org := SHORT(Files.Pos(r)); M := Modules.ThisMod(mods[eno]);
+      IF M # NIL THEN Cmd := Modules.ThisCommand(M, procs[eno]);
+        IF Cmd # NIL THEN Cmd END
+      END;
+      e := new;
+      IF e # NIL THEN e.W := ew; e.H := eh; e.base := T;
+        msg.pos := pos; e.handle(e, msg);
+        IF SHORT(Files.Pos(r)) # org + span THEN e := NIL END
+      END;
+      IF e = NIL THEN Files.Set(r, f, org + span);
+        NEW(a); a.W := ew; a.H := eh; a.handle := HandleAlien; a.base := T;
+        a.file := f; a.org := org; a.span := span;
+        a.mod := mods[eno]$; a.proc := procs[eno]$;
+        e := a
+      END
+    END LoadElem;
+
+  BEGIN pos := SHORT(Files.Pos(r)); f := Files.Base(r);
+    NEW(u); u.len := MAX(LONGINT); (*u.fnt := FontsDefault;*)u.fnt := NIL; u.col := Displaywhite;
+    T.head := u; ecnt := 0; fcnt := 0;
+    msg.id := load; msg.r := r;
+    Files.ReadInt(msg.r, hlen); (*!!!org := pos + hlen;*) org := pos -2 + hlen; pos := org; Files.ReadByte(msg.r, fno);
+    WHILE fno # 0 DO
+      IF fno > fcnt THEN fcnt := fno; Files.ReadString(msg.r, name); fnts[fno] := FontsThis(name) END;
+      Files.ReadByte(msg.r, col); Files.ReadByte(msg.r, voff); Files.ReadInt(msg.r, plen);
+      IF plen > 0 THEN NEW(p); p.file := f; p.org := pos; p.ascii := FALSE; un := p; un.len := plen
+      ELSE LoadElem(msg.r, pos - org, -plen, e); un := e; un.len := 1
+      END;
+      (*un.fnt := fnts[fno];*) un.col := col; un.voff := voff;
+      INC(pos, un.len); u.next := un; un.prev := u; u := un; Files.ReadByte(msg.r, fno)
+    END;
+    u.next := T.head; T.head.prev := u; T.cache := T.head; T.corg := 0;
+    Files.ReadInt(msg.r, T.len); Files.Set(r, f, SHORT(Files.Pos(msg.r)) + T.len)
+  END Load0;
+
+  PROCEDURE Load* (VAR r: Files.Rider; T: Text);
+    CONST oldTag = -4095;
+    VAR tag: INTEGER;
+  BEGIN
+    (* for compatibility inner text tags are checked and skipped; remove this in a later version *)
+    Files.ReadSInt(r, tag); IF tag # oldTag THEN Files.Set(r, Files.Base(r), Files.Pos(r)-2) END;
+    Load0(r, T)
+  END Load;
+
+  PROCEDURE Open* (T: Text; IN name: ARRAY OF CHAR);
+    VAR f: Files.File; r: Files.Rider; u: Run; p: Piece; tag, version, bom: CHAR; hlen: LONGINT;
+  BEGIN f := Files.Old(name);
+    IF f = NIL THEN f := Files.New("") END;
+    Files.Set(r, f, 0); Files.ReadChar(r, tag); Files.ReadChar(r, version);
+    IF (tag = textTag) OR (tag = 01X) & (version = textTag) THEN Load0(r, T)
+    ELSE (*ascii*)
+      NEW(u); u.len := MAX(LONGINT); u.fnt := NIL; u.col := Displaywhite;
+      NEW(p);
+      IF (tag = DocBlockId) & (version = 07X) THEN (* extract ascii text from System 3 text document *)
+        Files.Set(r, f, 28); Files.ReadInt(r, hlen);
+        Files.Set(r, f, 22 + hlen); Files.ReadInt(r, T.len); p.org := 26 + hlen
+      ELSE
+        T.len := SHORT(Files.Length(f));
+        (* checking isn't it UTF-8 encoded text with BOM? *)
+        Files.ReadChar(r, bom);
+        IF (tag = 0EFX) & (version = 0BBX) & (bom = 0BFX) THEN p.org := 3
+        ELSE p.org := 0
+        END;
+      END ;
+      IF T.len > 0 THEN p.len := T.len; p.fnt := FontsDefault;
+        p.col := Displaywhite; p.voff := 0; p.file := f; p.ascii := TRUE;
+        u.next := p; u.prev := p; p.next := u; p.prev := u
+      ELSE u.next := u; u.prev := u
+      END;
+      T.head := u; T.cache := T.head; T.corg := 0
+    END
+  END Open;
+
+  PROCEDURE Store* (VAR r: Files.Rider; T: Text);
+    VAR r1: Files.Rider; u, un: Run; e: Elem; org, pos, delta, hlen, rlen: LONGINT; ecnt, fno, fcnt: SHORTINT; ch: CHAR;  (* << *)
+      msg: FileMsg; iden: IdentifyMsg;
+      mods, procs: ARRAY 64, 32 OF CHAR;
+      fnts: ARRAY 32 OF FontsFont;
+      block: ARRAY 1024 OF CHAR;
+
+    PROCEDURE StoreElem (VAR r: Files.Rider; pos: LONGINT; e: Elem);
+      VAR r1: Files.Rider; org, span: LONGINT; eno: SHORTINT;
+    BEGIN mods[ecnt] := iden.mod$; procs[ecnt] := iden.proc$; eno := 1;
+      WHILE (mods[eno] # iden.mod) OR (procs[eno] # iden.proc) DO INC(eno) END;
+      Files.Set(r1, Files.Base(r), Files.Pos(r));
+      Files.WriteInt(r, 0); Files.WriteInt(r, 0); Files.WriteInt(r, 0); (*fixup slot*)
+      Files.WriteByte(r, eno);
+      IF eno = ecnt THEN INC(ecnt); Files.WriteString(r, iden.mod); Files.WriteString(r, iden.proc) END;
+      msg.pos := pos; org := SHORT(Files.Pos(r)); e.handle(e, msg); span := SHORT(Files.Pos(r)) - org;
+      Files.WriteInt(r1, -span); Files.WriteInt(r1, e.W); Files.WriteInt(r1, e.H) (*fixup*)
+    END StoreElem;
+
+  BEGIN
+    org := SHORT(Files.Pos(r)); msg.id := store; msg.r := r; Files.WriteInt(msg.r, 0); (*fixup slot*)
+    u := T.head.next; pos := 0; delta := 0; fcnt := 1; ecnt := 1;
+    WHILE u # T.head DO
+      IF u IS Elem THEN iden.mod[0] := 0X; u(Elem).handle(u(Elem), iden) ELSE iden.mod[0] := 1X END;
+      IF iden.mod[0] # 0X THEN
+        fnts[fcnt] := u.fnt; fno := 1;
+        WHILE fnts[fno].name # u.fnt.name DO INC(fno) END;
+        Files.WriteByte(msg.r, fno);
+        IF fno = fcnt THEN INC(fcnt); Files.WriteString(msg.r, u.fnt.name) END;
+        Files.WriteByte(msg.r, u.col); Files.WriteByte(msg.r, u.voff)
+      END;
+      IF u IS Piece THEN rlen := u.len; un := u.next;
+        WHILE (un IS Piece) & (un.fnt = u.fnt) & (un.col = u.col) & (un.voff = u.voff) DO
+          INC(rlen, un.len); un := un.next
+        END;
+        Files.WriteInt(msg.r, rlen); INC(pos, rlen); u := un
+      ELSIF iden.mod[0] # 0X THEN StoreElem(msg.r, pos, u(Elem)); INC(pos); u := u.next
+      ELSE INC(delta); u := u.next
+      END
+    END;
+    Files.WriteByte(msg.r, 0); Files.WriteInt(msg.r, T.len - delta);
+    (*!!!hlen := Files.Pos(msg.r) - org;*) hlen := SHORT(Files.Pos(msg.r)) - org + 2;
+    Files.Set(r1, Files.Base(msg.r), org); Files.WriteInt(r1, hlen); (*fixup*)
+    u := T.head.next;
+    WHILE u # T.head DO
+      IF u IS Piece THEN
+        WITH u: Piece DO
+          IF u.ascii THEN Files.Set(r1, u.file, u.org); delta := u.len;  (* << LF to CR *)
+            WHILE delta > 0 DO Files.ReadChar(r1, ch); DEC(delta);
+              IF ch = 0AX THEN Files.WriteChar(msg.r, CR) ELSE Files.WriteChar(msg.r, ch) END
+            END
+          ELSE Files.Set(r1, u.file, u.org); delta := u.len;
+            WHILE delta > LEN(block) DO
+              Files.ReadBytes(r1, s.THISARR(s.ADR(block), LEN(block)), LEN(block));
+              Files.WriteBytes(msg.r, s.THISARR(s.ADR(block), LEN(block)), LEN(block));
+              DEC(delta, LEN(block))
+            END;
+            Files.ReadBytes(r1, s.THISARR(s.ADR(block), LEN(block)), delta);
+            Files.WriteBytes(msg.r, s.THISARR(s.ADR(block), LEN(block)), delta)
+          END
+        END
+      ELSE iden.mod[0] := 0X; u(Elem).handle(u(Elem), iden);
+        IF iden.mod[0] # 0X THEN Files.WriteChar(msg.r, ElemChar) END
+      END;
+      u := u.next
+    END;
+    r := msg.r;
+    IF T.notify # NIL THEN T.notify(T, unmark, 0, 0) END
+  END Store;
+
+  PROCEDURE Close* (T: Text; IN name: ARRAY OF CHAR);
+    VAR f: Files.File; r: Files.Rider; i, res: LONGINT; bak: ARRAY 64 OF CHAR;
+  BEGIN
+    f := Files.New(name); Files.Set(r, f, 0); Files.WriteChar(r, textTag); Files.WriteChar(r, version); Store(r, T);
+    i := 0; WHILE name[i] # 0X DO INC(i) END;
+    bak := name$; bak[i] := "."; bak[i+1] := "B"; bak[i+2] := "a"; bak[i+3] := "k"; bak[i+4] := 0X;
+    Files.Rename(name, bak, res); Files.Register(f)
+  END Close;
+
+BEGIN del := NIL; NEW(FontsDefault); FontsDefault.name := "Syntax10.Scn.Fnt"
+END Texts.

src/edit.sh

@@ -1,2 +1,2 @@
 #!/bin/bash
-vim -p FreeOberon.Mod OV.Mod TermBox.Mod Graph2.Mod Allegro5.Mod
+vim -p FreeOberon.Mod FoStrings.Mod ../Data/Texts/en.dat OV.Mod TermBox.Mod Graph2.Mod Allegro5.Mod