(***************************************************************************)
(*                                                                         *)
(*           Zweite von drei Dateien des EUMEL-BASIC-Systems               *)
(*                                                                         *)
(*           Autor: Heiko Indenbirken                                      *)
(*           Überarbeitet von: Rudolf Ruland und Michael Overdick          *)
(*                                                                         *)
(*           Stand: 27.10.1987                                             *)
(*                                                                         *)
(***************************************************************************)

PACKET basic errors DEFINES basic error,      (* Autor: Heiko Indenbirken *)
                            return error,     (* Stand: 26.08.1987/rr/mo  *)
                            basic warning:

TEXT VAR erste zeile,
         message;
LET errorsize = 40;
LET ERROR = STRUCT (INT no, TEXT msg);

ROW errorsize ERROR CONST error msg :: ROW errorsize ERROR : 
(ERROR:( 1, "NEXT ohne FOR"),
 ERROR:( 2, "Syntaxfehler:"),
 ERROR:( 5, "Fehlerhafter Funktionsaufruf"),
 ERROR:( 8, "Zeile mit dieser Nummer existiert nicht"),
 ERROR:(10, "Das Feld ist bereits dimensioniert"),
 ERROR:(13, "Falscher Typ:"),
 ERROR:(15, "Text zu lang"),
 ERROR:(18, "Undefinierte 'user function'"),
 ERROR:(22, "Ausdruck erwartet"),
 ERROR:(26, "FOR ohne NEXT"),
 ERROR:(29, "WHILE ohne WEND"),
 ERROR:(30, "WEND ohne WHILE"),
 ERROR:(51, "Interner Fehler"),
 ERROR:(80, "Fehlerhafte Zeilennummer"),
 ERROR:(81, "Falsche Reihenfolge der Zeilennummern"),
 ERROR:(82, "Falscher Typ des Operanden:"),
 ERROR:(83, "Falscher Typ der Operanden:"),
 ERROR:(84, "Falsche Felddimension:"),
 ERROR:(85, "Rekursive Funktionsdefinition"), 
 ERROR:(86, "Fehlerhafte Laufvariable:"),
 ERROR:(87, "Fehlerhafte Bereichsangabe:"),
 ERROR:(88, "Fehlerhafte Dimensionierung:"),
 ERROR:(89, "Parametervariable kommt mehrmals vor"),
 ERROR:(90, "AS ohne NAME"),
 ERROR:(91, "BASE ohne OPTION"),
 ERROR:(92, "ELSE ohne IF"),
 ERROR:(93, "STEP ohne FOR"),
 ERROR:(94, "TAB ohne (L)PRINT"),
 ERROR:(95, "THEN ohne IF"),
 ERROR:(96, "TO ohne Zusammenhang"),
 ERROR:(97, "USING ohne (L)PRINT"),
 ERROR:(98, "Unbekannte Funktion,"),
 ERROR:(99, "Unbekannte Prozedur,"),
 ERROR:(100,"Nicht implementiert"),
 ERROR:(101,"SUB ohne GO"),
 ERROR:(102,"GO ohne TO oder SUB"),
 ERROR:(103,"Accessrecht VAR erwartet, CONST gefunden"),
 ERROR:(104,"Funktionsaufruf ohne Zusammenhang"),
 ERROR:(105,"Nach OPTION BASE ist nur 0 oder 1 erlaubt"),
 ERROR:(106,"Bei SWAP nur gleiche Variablentypen erlaubt"));

TEXT PROC errortext (INT CONST no):
  INT VAR i;
  FOR i FROM 1 UPTO errorsize
  REP IF errormsg [i].no = no
      THEN LEAVE errortext WITH errormsg [i].msg FI
  PER;
  "Unbekannter BASIC-Fehler #" + text (no)  .
END PROC errortext;

PROC basic error (TEXT CONST packet,
                  INT CONST error nr,
                  INT CONST line nr,
                  INT CONST statement nr,
                  TEXT CONST position, addition,
                  BOOL CONST leave statement):
  erste zeile aufbauen;
  einfache fehlermeldung aufbauen; 
  diese auf terminal ausgeben; 
  diese in sysout datei ausgeben wenn noetig;                    (* F20/rr *)
  fehlermeldung in fehlerdatei ausgeben;
  IF leave statement                                             (* DEF/mo *)
    THEN errorstop (101, packet + "-Fehler")
  FI.

erste zeile aufbauen:
  IF line nr = 0 AND statement nr = 0
  THEN erste zeile := "FEHLER"
  ELSE erste zeile := "FEHLER (Dateizeile ";
       erste zeile CAT text (line nr);
       erste zeile CAT ") in Zeile ";
       erste zeile CAT text (statement nr);
  FI;
 
  erste zeile CAT " bei >> ";
  erste zeile CAT position;
  erste zeile CAT " << : "  .

einfache fehlermeldung aufbauen:
  message := "   ";
  message CAT error text (error nr);
  message CAT "   "  .
 
diese auf terminal ausgeben:                                     (* F20/rr *)
  display (""13""10"");
  display (erste zeile);
  display (""13""10"");
  display (message + addition);
  display (""13""10"") .
 
diese in sysout datei ausgeben wenn noetig :                      (* F20/rr *)
  IF sysout <> ""
     THEN putline (erste zeile);
          putline (message + addition);
          line;
  FI .

fehlermeldung in fehlerdatei ausgeben:
  note (erste zeile);
  note line;
  note (message);
  note (addition);
  note line .
 
END PROC basic error;

PROC basic warning (INT CONST line nr,                   (* mo *)
                              statement nr,
                    TEXT CONST warning text):
generate warning;
on screen;
in sysout file;
into the notebook.

generate warning:
  IF line nr = 0 AND statement nr = 0
  THEN erste zeile := "WARNUNG"
  ELSE erste zeile := "WARNUNG (Dateizeile ";
       erste zeile CAT text (line nr);
       erste zeile CAT ") in Zeile ";
       erste zeile CAT text (statement nr);
  FI;
  erste zeile CAT ": ";
  erste zeile CAT warning text.

on screen:
  display (""13""10"");
  display (erste zeile);
  display (""13""10"").

in sysout file:
  IF sysout <> ""
     THEN putline (erste zeile);
          line;
  FI.

into the notebook:
  IF warnings
    THEN note (erste zeile);
         note line
  FI.

END PROC basic warning;

PROC return error:
  errorstop (1003, "RETURN ohne GOSUB")
END PROC return error;

END PACKET basic errors;

PACKET basic types DEFINES symbol of,         (* Autor: Heiko Indenbirken *)
                           type of,           (* Stand: 07.09.1987/rr/mo  *)
                           dim of,
                           shift, deshift,
                           reserved,
                           param list,
                           is bool op:

LET (*                 S y m b o l    T y p e n                          *)
    any      =  0,    const    =  1,    var     =  2,    array    =  3,
    expr     =  4,    unused   =  5,    letter  =  6,    param    =  7,
    res word =  8,    operator =  9,    eos     = 10,    del      = 11,
    stat no  = 12,    eol      = 13,    eop     = 14,
    user fn  = 20;  (* DEF/mo *)
(*                               Operatoren                              *)
LET less equal = 28,  unequal = 29,  greater equal = 30;

TEXT VAR dummy;
 
TEXT PROC symbol of (INT CONST n) :
  IF n < 0
  THEN ""19"" + symbol of (-n)
  ELSE SELECT n OF
       CASE less equal    : "<="
       CASE unequal       : "<>"
       CASE greater equal : ">="

       CASE eos           : "EOS"
       CASE eol           : "EOL"
       CASE eop           : "EOF"
       OTHERWISE : character END SELECT
  FI  . 

character :
  IF n > 32 AND n < 128
  THEN code (n)
  ELIF n >= 128 AND n <= 255
  THEN res word of (n)
  ELSE "%" + subtext (text (n+1000), 2) + " " FI  .

END PROC symbol of;

TEXT PROC type of (INT CONST n) :
  SELECT n OF
  CASE any      : "ANY"
  CASE const    : "Konstante"
  CASE var      : "Variable"
  CASE array    : "Feld"
  CASE expr     : "Ausdruck"
  CASE unused   : " -?- "
  CASE letter   : "Buchstabe" 
  CASE param    : "Parameter"
  CASE res word : "reserviertes Wort"
  CASE operator : "Operator"
  CASE eos      : "EOS"
  CASE del      : "Trennzeichen"
  CASE stat no  : "Zeilennumer"
  CASE eol      : "EOL"
  CASE eop      : "EOF"
  CASE user fn  : "'user function'"                   (* DEF/mo *)
  OTHERWISE "?TYPE #" + text (n) ENDSELECT.
END PROC type of;

TEXT PROC dim of (TEXT CONST parameter):
  IF parameter = ""
  THEN ""
  ELSE base limits and size FI  .

base limits and size:
  INT CONST dimension :: (LENGTH parameter DIV 2) - 2;
  TEXT VAR result :: text (parameter ISUB dimension+1);
  INT VAR i;
  result CAT ": [";
  FOR i FROM 1 UPTO dimension-1
  REP result CAT text (parameter ISUB i);
      result CAT ", "
  PER;
  result CAT text (parameter ISUB dimension);
  result CAT "]  ";
  result CAT text (parameter ISUB dimension+2);
  result  .

END PROC dim of;

TEXT PROC param list (INT CONST first, no):
  IF no < first
  THEN "keine"
  ELSE parameter list FI  .

parameter list:
  INT VAR i;
  TEXT VAR result :: "(";
  FOR i FROM first UPTO no
  REP result CAT dump (dtype (i));
      IF i = no
         THEN result CAT ")"
         ELSE result CAT ", " FI
  PER;
  result  .

END PROC param list;

TEXT PROC shift (TEXT CONST word) :
  INT VAR i;
  dummy := word;
  FOR i FROM 1 UPTO length (word)
  REP shift char PER;
  dummy  .

shift char:
  INT VAR local letter :: code (dummy SUB i);
  IF 97 <= local letter AND local letter <= 122
  THEN replace (dummy, i, code (local letter - 32)) FI  .

END PROC shift;

TEXT PROC deshift (TEXT CONST word) :
  INT VAR i;
  dummy := word;
  FOR i FROM 1 UPTO length (word)
  REP deshift char PER;
  dummy  .

deshift char:
  INT VAR local letter :: code (dummy SUB i);
  IF 65 <= local letter AND local letter <= 90
  THEN replace (dummy, i, code (local letter + 32)) FI;

END PROC deshift;

(*                Verwaltung der Reservierten BASIC-Wörter               *)
LET first operator = 249,             (* MOD  NOT  AND   OR  XOR  EQV  IMP *)
    first bool op  = 250;             (* 249  250  251  252  253  254  255 *)

INT VAR index;
ROW 9 TEXT VAR res words :: ROW 9 TEXT :
("",
 ""129"as"163"go"167"if"188"on"217"to"252"or",
 ""128"abs"130"asc"131"atn"141"cos"142"cvd"143"cvi"145"def"150"dim"152"end"153"eof"154"erl"155"err"157"exp"159"fix"160"for"161"fre"162"get"172"int"175"len"176"let"178"loc"179"log"191"out"192"pos"194"put"202"rnd"197"rem"204"sgn"205"sin"207"spc"208"sqr"214"tab"215"tan"221"val"227"cls"234"usr"235"sub"249"mod"250"not"251"and"253"xor"254"eqv"255"imp",
 ""132"base"133"call"134"cdbl"136"chr$"137"cint"144"data"151"else"165"goto"166"hex$"173"kill"177"line"181"lset"182"mid$"183"mkd$"184"mki$"185"name"186"next"187"oct$"189"open"196"read"203"rset"209"step"210"stop"211"str$"213"swap"216"then"219"tron"222"wait"223"wend"228"erm$"230"lpos",
 ""135"chain"138"clear"139"close"156"error"158"field"164"gosub"169"input"171"instr"174"left$"193"print"218"troff"220"using"224"while"225"width"226"write"231"time$"232"date$"233"timer",
 ""140"common"146"defdbl"147"defint"148"defsng"149"defstr"168"inkey$"170"input$"180"lprint"190"option"199"resume"200"return"201"right$"206"space$"229"csrlin",
 ""198"restore"212"string$",
 "",
 ""195"randomize");

BOOL PROC reserved (TEXT CONST name, INT VAR no, type):
  IF reserve is not possible COR not found within res words
  THEN FALSE
  ELSE no   := code (this words SUB (index-1));
       type := res word or op;
       TRUE
  FI  .

reserve is not possible:
  INT CONST len :: length (name);
  len < 2 OR len > 9  .

not found within res words:
  index := pos (this words, name);
  index = 0  .

this words:
  res words [len]  .

res word or op:
  IF no >= first operator
  THEN operator
  ELSE res word FI  .

END PROC reserved;

INT PROC reserved (TEXT CONST name):
  IF reserve is not possible COR not found within res words
  THEN 0
  ELSE code (this words SUB (index-1)) FI  .

reserve is not possible:
  INT CONST len :: length (name);
  len < 2 OR len > 9  .

not found within res words:
  index := pos (this words, name);
  index = 0  .

this words:
  res words [len]  .

END PROC reserved;

TEXT PROC res word of (INT CONST no):
  INT VAR i;
  FOR i FROM 2 UPTO 9
  REP index := pos (res words [i], code (no));
      IF index > 0
      THEN LEAVE res word of WITH shift (this name) FI
  PER;
  ""  .

this name:
  subtext (res words [i], index+1, next code)  .

next code:
  INT VAR c := pos (res words [i], ""127"", ""255"", index+1);
  IF c = 0
  THEN length (res words [i])
  ELSE c-1 FI  .

END PROC res word of;

BOOL PROC is bool op (INT CONST no):            (* mo *)
  no >= first bool op
END PROC is bool op;

END PACKET basic types;

PACKET basic table handling DEFINES init table, (* Autor: Heiko Indenbirken *)
                              put name,         (* Stand: 13.08.1987/rr/mo  *)
                              known, name of,
                              remember,
                              recognize,
                              table entries,
                              hash table, next table,
                              scope compulsory:          (* DEF/mo *)

LET hash length = 1024, 
    hash length minus one = 1023,
    start of name table = 256,
    table length = 4500;
 
LET SYMBOL = STRUCT (INT type, ADDRESS adr, DTYPE data, TEXT dim);
LET TABLE = STRUCT (INT entries,
                    ROW hash length INT hash table,
                    ROW table length INT next, 
                    ROW table length TEXT name table,
                    ROW table length SYMBOL symbol table);
 
DATASPACE VAR table space;
BOUND TABLE VAR table;
INITFLAG VAR tab := FALSE;
SYMBOL CONST nilsymbol :: SYMBOL:(0, LOC 0, void type, "");
INT VAR i;
BOOL VAR compulsory with scope :: TRUE;                     (* DEF/mo *)

PROC init table:
  IF NOT initialized (tab)
  THEN table space := nilspace;
       table := table space;
  FI;
  table.entries := start of name table;
  FOR i FROM 1 UPTO hash length
  REP table.hash table [i] := 0 PER;
  compulsory with scope := TRUE;                            (* DEF/mo *)

END PROC init table;

PROC put name (TEXT CONST scope, name, INT VAR pointer):    (* DEF/mo *)
  IF compulsory with scope
    THEN put name (scope + name, pointer)
  ELIF NOT in table
    THEN put name (name, pointer)
  FI.

in table:
  hash (scope + name, pointer);
  pointer := hash table (pointer);
  WHILE not end of chain
  REP IF name is found THEN LEAVE in table WITH TRUE FI;
      pointer := table. next (pointer);
  PER;
  FALSE .

name is found:
  table.name table [pointer] = scope + name.
 
not end of chain:
  pointer > 0  .

END PROC put name;

PROC put name (TEXT CONST name, INT VAR pointer):
  IF no entry in hash table
  THEN create a new chain
  ELSE create a new entry in chain FI;
  insert name in name table  .
 
no entry in hash table:
  INT VAR hash index;
  hash (name, hash index); 
  table.hash table [hash index] = 0  .

create a new chain:
  table.hash table [hash index] := table.entries  .
 
create a new entry in chain:
  pointer := table.hash table [hash index];
  REP IF name is found
      THEN LEAVE put name
      ELIF end of chain
      THEN table.next [pointer] := table.entries;
           LEAVE create a new entry in chain
      ELSE pointer := next pointer FI
  PER  .
 
name is found:
  table.name table [pointer] = name.
 
end of chain:
  INT CONST next pointer := table.next [pointer];
  next pointer = 0  .

insert name in name table:
  IF table.entries >= table length 
  THEN errorstop ("volle Namenstabelle") FI;

  pointer := table.entries;
  table.symbol table [pointer] := nilsymbol;
  table.name table [pointer] := name; 
  table.next [pointer] := 0; 
  table.entries INCR 1  .

END PROC put name; 

PROC hash (TEXT CONST name, INT VAR index) :
  INT VAR j;
  index := 0;
  FOR j FROM 1 UPTO length (name)
  REP addmult cyclic PER;
  index INCR 1  .
 
addmult cyclic :
  index INCR index ;
  IF index > hash length minus one
  THEN wrap around FI;
  index := (index + code (name SUB j)) MOD hash length minus one  .

wrap around:
  index DECR hash length minus one  .

ENDPROC hash ;
 
INT PROC table entries:
  table.entries
END PROC table entries;

INT PROC hash table (INT CONST n):
  table.hash table [n]
END PROC hash table;

INT PROC next table (INT CONST n):
  table.next [n]
END PROC next table;

TEXT PROC name of (INT CONST index): 
  IF index < 0
  THEN errorstop ("PROC name of: negativer Index"); ""
  ELIF index < start of name table
  THEN symbol of  (index)
  ELIF index <= table.entries
  THEN table.name table (index) 
  ELSE errorstop ("PROC name of: Index größer als nametable");
       ""
  FI

END PROC name of; 
 
PROC recognize (INT CONST symb, type, ADDRESS CONST adr, DTYPE CONST data, TEXT CONST dim):
  symbol.type  := type;
  symbol.adr   := adr;
  symbol.data  := data; 
  symbol.dim   := dim  .

symbol: table.symboltable [symb]  .
END PROC recognize;

PROC remember (INT CONST symb, INT VAR type, ADDRESS VAR adr, DTYPE VAR data, TEXT VAR dim):
  SYMBOL CONST symbol := table.symboltable [symb];
  type  := symbol.type;
  adr   := symbol.adr;
  data  := symbol.data; 
  dim   := symbol.dim
END PROC remember;

BOOL PROC known (INT CONST symb) :
  table.symboltable [symb].type > 0
END PROC known;

PROC scope compulsory (BOOL CONST new state):       (* DEF/mo *)
  compulsory with scope := new state
END PROC scope compulsory;

END PACKET basic table handling;

PACKET basic scanner DEFINES begin scanning,  (* Autor: Heiko Indenbirken *)
                             next symbol,     (* Stand: 27.10.1987/rr/mo  *)
                             next data,
                             next statement,
                             define chars,
                             scan line,
                             scan line no,                       (* F29/rr *)
                             get data types of input vars,       (* F25/rr *)
                             basic error,
                             basic warning,
                             basic list,
                             set scope,
                             scanner scope:


LET (*                    S y m b o l    T y p e n                       *)
    any     = 0,  const   = 1,  var     = 2,  array   = 3,
    res word= 8,  operator= 9,  eos     = 10, del     =11,
    stat no = 12, user fn = 20;         (* DEF/mo *)

LET (*                    S y m b o l z e i c h e n                      *)
    less         = 60,  greater       = 62,
    less equal   = 28,  unequal       = 29,  greater equal = 30, 
    point        = 46,  eol           = 13,  eop           = 14,
    go           = 163, gosub         = 164, goto          = 165,
    sub          = 235, to            = 217;

LET name chars    = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz.0123456789!#$%",
    quote         = """",       open bracket    = "(",
    comma         = ",",        close bracket   = ")",
    colon         = ":",
    exponent chars= "dDeE";

FILE VAR source file;
TEXT VAR defint chars, defstr chars, record, letter,
         scope, new name;     (* DEF/mo *)
REAL VAR r dummy;
INT VAR act stat no, record no, rec len, scan pos, i dummy;
BOOL VAR eol generated, at line begin, listing := FALSE;

PROC define chars (TEXT CONST begin, end, DTYPE CONST data):
  INT VAR i;
  FOR i FROM code (begin) UPTO code (end)
  REP IF data = int type
        THEN defint chars CAT code (i) 
      ELIF data = text type
        THEN defstr chars CAT code (i) 
      FI
  PER  .

END PROC define chars;


PROC scanline (TEXT VAR line, INT VAR col):
  line := record;
  col  := scan pos
END PROC scanline;

INT PROC scan line no : record no END PROC scan line no;


PROC get data types of input vars (ROW 100 DTYPE VAR input var data, (* F25/rr *)
                                   INT VAR number input vars) :

  TEXT VAR first var char;
  INT VAR var pos := scan pos;
  to begin of actual var;
  REP get next input var;
      skip brackets if necessary;
      IF var char <> comma THEN LEAVE get data types of input vars FI;
      skip comma;
  PER;
 
  . var char : record SUB var pos

  . to begin of actual var :
      WHILE pos (name chars, var char) <> 0 REP var pos DECR 1 PER;
      var pos         INCR 1;
      number input vars := 0;
 
  . get next input var :
      first var char := deshift (var char);
      WHILE pos (name chars, var char) <> 0 REP var pos INCR 1 PER;
      var pos           DECR 1;
      number input vars INCR 1;
      input var data (number input vars) := var datatype (first var char, var char);
      var pos := pos (record, ""33"", ""255"", var pos + 1);

  . skip brackets if necessary :
      IF var char =  open bracket
         THEN INT VAR bracket counter := 1;
              REP count bracket UNTIL bracket counter = 0 PER;
              var pos := pos (record, ""33"", ""255"", var pos + 1);
      FI;

      . count bracket :
          INT CONST open  := pos (record, open  bracket, var pos + 1),
                    close := pos (record, close bracket, var pos + 1);
          IF open > 0
             THEN IF close > 0
                     THEN IF open > close
                             THEN close bracket found
                             ELSE open  bracket found
                          FI;
                     ELSE open bracket found
                  FI;
             ELSE IF close > 0
                     THEN close bracket found
                     ELSE LEAVE get data types of input vars 
                  FI;
          FI;

          . open bracket found :
               bracket counter INCR 1;
               var pos := open;

          . close bracket found :
               bracket counter DECR 1;
               var pos := close;

  . skip comma :
      var pos := pos (record, ""33"", ""255"", var pos + 1);

END PROC get data types of input vars;


PROC begin scanning (FILE VAR basic file):
  enable stop;
  source file := basic file;
  to first record (source file);
  col (source file, 1);
  IF eof (source file) 
  THEN errorstop ("Datei ist leer") FI; 

  defint chars := "";
  defstr chars := ""; 
  scope := "";                              (* DEF/mo *)
  act stat no := 0;
  read record (source file, record); 
  rec len := length (record);
  scan pos := 0; 
  record no := 1;
  eol generated := FALSE;
  at line begin := TRUE;
  IF listing
    THEN line;
         putline (record);
         IF sysout <> ""
           THEN cout (record no)
         FI
    ELSE cout (record no)
  FI.

END PROC begin scanning;
 
PROC next statement:
  IF eof (source file)
  THEN errorstop (99, "")
  ELSE eol generated := FALSE;
       at line begin := TRUE;
       down (source file);
       read record (source file, record); 
       rec len := length (record);
       scan pos := 0; 
       record no INCR 1;
  FI;
  IF listing
    THEN putline (record);
         IF sysout <> ""
           THEN cout (record no)
         FI
    ELSE cout (record no)
  FI.
  
END PROC next statement;

PROC next symbol (TEXT VAR name, INT VAR no, type, DTYPE VAR data):
  enable stop;
  clear symbol;
  IF eol generated
  THEN next statement FI;

  IF eol reached
  THEN generate eol
  ELIF at line begin CAND stat no found                          (* F15/rr *)
  THEN generate stat no
  ELSE generate chars FI  .

clear symbol:
  name := "";
  no   := 0;
  type := any;
  data := void type  .
 
eol reached:
  scan pos := pos (record, ""33"", ""255"", scan pos+1); 
  scan pos = 0  .

generate eol :
  IF eof (source file)
  THEN name := "EOF";  no := eop;  type := eos
  ELSE name := "EOL";  no := eol;  type := eos FI;
  eol generated := TRUE  .

stat no found:                                                   (* F15/rr *)
  at line begin := FALSE;
  pos ("0123456789", act char) <> 0 .
 
generate stat no:                                                (* F15/rr *)
  INT CONST next scan pos := last number pos;
  name        := subtext (record, scan pos, next scan pos);
  act stat no := int (name);
  scan pos    := next scan pos;
  no := act stat no;  type := stat no  .

last number pos :                                                (* F15/rr *)
  INT CONST high := pos (record, ""058"", ""255"", scan pos),
            low  := pos (record, ""032"", ""047"", scan pos);
  IF   high > 0
       THEN IF low > 0
               THEN min (high, low) - 1
               ELSE high - 1
            FI
  ELIF low > 0
       THEN low - 1
       ELSE LENGTH record
  FI .

generate chars:
  SELECT code (act char) OF
  CASE 32: next symbol (name, no, type, data)            (* Space        *) 
  CASE 34: generate text denoter                         (* "            *) 
  CASE 39: generate eol                                  (* '            *)
  CASE 42, 43, 45, 47, 92, 94, 61: generate operator     (* *,+,-,/,\,^,=*)
  CASE 60: generate less op                              (*<, <=, <>     *) 
  CASE 62: generate greater op                           (*>, >=         *)
  CASE 46: treat point                                   (* .            *)
  CASE 48, 49, 50, 51, 52, 53, 54, 55, 56, 57: 
           generate numeric const                        (* 0  -  9      *)
  CASE 58: generate eos                                  (* :            *)
  CASE 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81,
       82, 83, 84, 85, 86, 87, 88, 89, 90,  97, 98, 99, 100, 101, 102, 103,
       104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117,
       118, 119, 120, 121, 122,               (* small and large letters *)
       generate res word or id
  OTHERWISE generate delimiter END SELECT  .

generate text denoter:
  get text const (name, data);
  type := const  .

generate operator:
  name := act char;  no := code (name);  type := operator  .

generate less op:
  IF next char = "="
  THEN name := "<=";  no := less equal; skip char
  ELIF next char = ">"
  THEN name := "<>";  no := unequal;    skip char
  ELSE name := "<";  no := less FI;
  type := operator  .

generate greater op:
  IF next char = "="
  THEN name := ">=";  no := greater equal;  skip char 
  ELSE name := ">";  no := greater;  FI;
  type := operator  .

treat point:
  IF pos ("0123456789", next char) <> 0
    THEN generate numeric const
    ELSE name := ".";
         no := point;
         type := del
  FI.

generate numeric const:
  get numeric const (name, data);
  type := const  .

last name char:
  name SUB LENGTH name  .

generate eos:
  name := ":";  no := eos;  type := eos  .

generate res word or id:
  get name chars;
  IF reserved (deshift name, no, type)
    THEN IF type = res word AND no = go
           THEN treat go
         FI
    ELSE IF function name
           THEN data := ftn datatype;
                type := user fn
           ELSE data := var datatype (deshift (name) SUB 1, last name char);
                type := var or array
         FI;
         put name (scope, deshift name, no)
  FI.

treat go:
  next symbol (new name, no, type, data);
  IF no = to AND type = res word
    THEN name CAT new name;
         no := goto
  ELIF no = sub AND type = res word
    THEN name CAT new name;
         no := gosub
    ELSE scan error (102, name, "")
  FI.

get name chars:
  TEXT VAR deshift name :: "";
  INT VAR begin of name :: scan pos;
  FOR scan pos FROM scan pos UPTO rec len
  WHILE name chars found
  REP deshift name CAT deshifted char PER;
  scan pos DECR 1;
  name := subtext (record, begin of name, scan pos).

name chars found:
  pos (name chars, act char) > 0  .

function name:
  subtext (deshift name, 1, 2) = "fn"  .

ftn datatype:
  IF last name char = "$"
  THEN text type
  ELIF last name char = "%"
  THEN int type
  ELSE real type FI  .

var or array:
  IF array name
  THEN name CAT "()";
       deshift name CAT "()";                                (* F30/rr *)
       array
  ELSE var FI  .

array name:
  next scan char = "("  .

deshifted char:
  letter := act char;
  IF letter >= "A" AND letter <= "Z"
  THEN code (code (letter) + 32)
  ELSE letter FI  .

generate delimiter:
  name := act char;  no := code (name);  type := del  .

next scan char: record SUB pos (record, ""33"", ""255"", scan pos+1). 
next char: (record SUB scan pos + 1)  .
act char: record SUB scan pos  .
skip char:  scan pos INCR 1  .
END PROC next symbol;

DTYPE PROC var datatype (TEXT CONST first name char, last name char) :

  IF last name char = "!" OR last name char = "#"
  THEN real type
  ELIF last name char = "$"
  THEN text type
  ELIF last name char = "%"
  THEN int type
  ELIF pos (defint chars, first name char) > 0
  THEN int type
  ELIF pos (defstr chars, first name char) > 0
  THEN text type
  ELSE real type FI  .

END PROC var datatype;

BOOL PROC next data (TEXT VAR data text, DTYPE VAR data type) :  (* F17/rr *)

  data type := void type;
  IF   no more data
       THEN scan pos  := rec len;
            data text := "";
            FALSE
  ELIF quoted string
       THEN get quoted string;
            TRUE
       ELSE get unquoted string;
            TRUE
  FI

  . no more data :
      scan pos := pos (record, ""33"", ""255"", scan pos+1);
      scan pos = 0

  . quoted string :
      (record SUB scan pos) = quote

  . get quoted string :
      get text const (data text, data type);

  . get unquoted string :
      INT CONST comma or colon pos 1 := position of comma or colon minus one;
      data text := compress (subtext (record, scan pos, comma or colon pos 1));
      scan pos  := comma or colon pos 1;

  . position of comma or colon minus one :
      INT CONST colon pos := pos (record, colon, scan pos),
                comma pos := pos (record, comma, scan pos);
      IF colon pos > 0
         THEN IF comma pos > 0
                 THEN min (colon pos, comma pos) - 1
                 ELSE colon pos - 1
              FI
         ELSE IF comma pos > 0
                 THEN comma pos - 1
                 ELSE LENGTH record
              FI
      FI

END PROC next data;

PROC get numeric const (TEXT VAR value, DTYPE VAR data):
  get sign;
  get const;
  check datatype  .

get sign:
  IF act char = "-"
  THEN value := "-";
       scan pos INCR 1
  ELIF act char = "+"
  THEN value := "+";
       scan pos INCR 1
  ELSE value := "" FI  .

get const:
  get digits;
  get point;
  get digits;
  get exponent  .

get digits:
  FOR scan pos FROM scan pos UPTO rec len
  WHILE digit found
  REP value CAT act char PER  .

get point:
  IF act char = "."
  THEN value CAT ".";
       scan pos INCR 1
  ELIF pos (exponent chars, act char) > 0
  THEN value CAT ".0"
  ELSE LEAVE get const FI  .

get exponent:
  IF pos (exponent chars, act char) > 0                 (* F1/rr *)
  THEN value CAT "e";
       scan pos INCR 1;
       evtl get sign;
       get digits
  FI  .

evtl get sign:
  IF act char = "+" OR act char = "-"
  THEN value CAT act char;
       scan pos INCR 1
  FI  .

digit found:
  "0" <= act char AND act char <= "9"  .

check datatype:
  IF act char = "%" 
  THEN IF integer ok (value)
       THEN data := int type
       ELSE scan error (2, value, "INT-Konstante nicht korrekt") FI
  ELIF act char = "!" OR act char = "#"
  THEN IF real ok (value)
       THEN data := real type
       ELSE scan error (2, value, "REAL-Konstante nicht korrekt") FI
  ELIF integer ok (value)
  THEN scan pos DECR 1;  data := int type
  ELIF real ok (value)
  THEN scan pos DECR 1;
       data := real type
  ELSE scan error (2, value, "Numerische Konstante nicht korrekt") FI  . 

act char: record SUB scan pos  .
END PROC get numeric const;
 
PROC get text const (TEXT VAR value, DTYPE VAR data):
  INT CONST quote 1 := scan pos;
  scan pos := pos (record, """", scan pos+1);
  IF quote 1 < scan pos
  THEN value := subtext (record, quote 1+1, scan pos-1);
       data := text type
  ELSE scan error (15, subtext (record, quote 1), "("" fehlt)") FI  .

END PROC get text const;

BOOL PROC integer ok (TEXT VAR zahl):
  disable stop;
  i dummy := int (zahl);
  IF is error
  THEN clear error;
       FALSE
  ELIF last conversion ok
  THEN zahl := ""0""0"";
       replace (zahl, 1, i dummy);
       TRUE
  ELSE FALSE FI  .

END PROC integer ok;

BOOL PROC real ok (TEXT VAR zahl):
  disable stop;
  r dummy := real (zahl);
  IF is error
  THEN clear error;
       FALSE
  ELIF last conversion ok
  THEN zahl := ""0""0""0""0""0""0""0""0"";
       replace (zahl, 1, r dummy);
       TRUE
  ELSE FALSE FI  .

END PROC real ok;

PROC basic error (INT CONST no, TEXT CONST name, addition):
  basic error ("Compiler", no, record no, act stat no, name, addition, TRUE)
END PROC basic error;

PROC basic error (INT CONST no, TEXT CONST name, addition, BOOL CONST leave statement):
  basic error ("Compiler", no, record no, act stat no, name, addition, leave statement)
END PROC basic error;

PROC scan error (INT CONST no, TEXT CONST name, addition):
  basic error ("Scanner", no, record no, act stat no, name, addition, TRUE)
END PROC scan error;

PROC basic warning (TEXT CONST warning text):               (* mo *)
  basic warning (record no, act stat no, warning text)
END PROC basic warning;

PROC basic list (BOOL CONST t):
  listing := t 
END PROC basic list;

BOOL PROC basic list:
  listing
END PROC basic list;

PROC set scope (TEXT CONST new scope):                          (* DEF/mo *)
  scope := new scope
END PROC set scope;

TEXT PROC scanner scope:                                        (* DEF/mo *)
  scope
END PROC scanner scope;

END PACKET basic scanner;


PACKET basic stat no DEFINES init stat no,    (* Autor: Heiko Indenbirken *)
                             stat no pos,     (* Stand: 27.10.1987/rr/mo  *)
                             label pos,
                             all stat no:

LET nil = "";

TEXT VAR found stat no :: nil;
INT VAR i, akt stat no :: 0, found no :: 0;

PROC init stat no (FILE VAR f, INT VAR error no):                (* F21/rr *)
(*Die Datei 'f' muß im 'modify-Mode' sein.                               *)
  INT VAR line no;
  akt stat no := -1;                                             (* F28/rr *)
  found no := 0;
  found stat no := nil;
  error no := 0;                                                 (* F21/rr *)
  to first record (f);
  col (f, 1);
  disable stop;
  FOR line no FROM 1 UPTO 4000
  REP exec (PROC (TEXT CONST, INT CONST) check, f, line no);
      IF is error THEN check error FI;
      IF eof (f)
      THEN LEAVE init stat no
      ELSE down (f) FI
  PER;

. check error :                                                  (* F21/rr *)
    IF error code = 100
       THEN clear error;
            error no INCR 1;
       ELSE LEAVE init stat no;
    FI;

END PROC init stat no;

PROC check (TEXT CONST record, INT CONST line no):
  IF statement no vorhanden
  THEN remember statement no FI  .

statement no vorhanden:                                          (* F15/rr *)
   INT CONST first number pos := pos (record, ""048"", ""057"", 1);
   first number pos > 0 CAND first number pos = first non blank pos .

first non blank pos :                                            (* F15/rr *)
   pos (record, ""033"", ""255"", 1) .

remember statement no:
  get statement no;
  IF neue nummer ist groesser als vorherige
  THEN akt stat no := neue nummer;
       cout (neue nummer);
       found no INCR 1;
       found stat no CAT mki (neue nummer)
  ELSE basic error ("Stat no", 81, line no, neue nummer, number,
                    "Letzte Zeilennummer davor: " + text (akt stat no), TRUE)
  FI  .

get statement no :                                               (* F15/rr *)
  disable stop;
  TEXT CONST number := subtext (record, first number pos, last number pos);
  INT VAR neue nummer := int (number);
  IF NOT last conversion ok OR is error
  THEN clear error;
       basic error ("Stat no", 80, line no, akt stat no, number,
                    "Die Zeilennummer muß im Bereich 0-32767 liegen", TRUE)
  FI;
  enable stop .

last number pos :                                                (* F15/rr *)
  INT CONST high := pos (record, ""058"", ""255"", first number pos),
            low  := pos (record, ""032"", ""047"", first number pos);
  IF   high > 0
       THEN IF low > 0
               THEN min (high, low) - 1
               ELSE high - 1
            FI
  ELIF low > 0
       THEN low - 1
       ELSE LENGTH record
  FI .

neue nummer ist groesser als vorherige:
  neue nummer > akt stat no  .

END PROC check;

INT PROC stat no pos (INT CONST stat no):
  FOR i FROM found no DOWNTO 1
  REP IF (found stat no ISUB i) = stat no
      THEN LEAVE stat no pos WITH i FI
  PER;
  0
END PROC stat no pos;

INT PROC label pos (INT CONST stat no):
  FOR i FROM found no DOWNTO 1
  REP IF (found stat no ISUB i) = stat no
      THEN LEAVE label pos WITH i FI
  PER;
  basic error (8, text (stat no), nil);                         (* F16/rr *)
  0
END PROC label pos;

PROC all stat no (TEXT VAR stat no, INT VAR no):
  stat no := found stat no;
  no      := found no
END PROC all stat no;

END PACKET basic stat no;

PACKET basic storage DEFINES init storage,     (* Autor: Heiko Indenbirken *)
                             next local adr,   (* Stand: 12.06.86          *)
                             next ref,
                             local adr,
                             local storage,
                             type size,
                             quiet type:         
                                              
                                              

LET ref length = 2;

INT VAR quiet size, quiet align;
ADDRESS VAR loc adr, free loc adr;
DTYPE VAR quiet value;
identify ("QUIET", quiet size, quiet align, quiet value);

PROC init storage:
  free loc adr := LOC 0;
  loc adr      := LOC 0;

END PROC init storage;

(*        Verwaltung der lokalen Addressen für Zwischenergebnisse        *)
ADDRESS PROC next local adr (DTYPE CONST type):
  INT VAR type len :: type size (type);
  loc adr := free loc adr;
  adjust (loc adr, type len);
  free loc adr := loc adr + type len;
  loc adr  .

END PROC next local adr;

ADDRESS PROC next ref:
  loc adr := free loc adr;
  adjust (loc adr, ref length);
  free loc adr := loc adr + ref length;
  loc adr  .

END PROC next ref;

ADDRESS PROC local adr:
   loc adr
END PROC local adr;

INT PROC local storage:
  int (subtext (dump (free loc adr), 6))
END PROC local storage;

INT PROC type size (DTYPE CONST type):
   IF type = int type OR type = bool type
   THEN 1
   ELIF type = row type
   THEN 2
   ELIF type = real type
   THEN 4
   ELIF type = text type
   THEN 8
   ELIF type = quiet value
   THEN quiet size
   ELSE errorstop ("Unbekannter DTYPE: " + dump (type));  0 FI  .

END PROC type size;

DTYPE PROC quiet type:
  quiet value
END PROC quiet type;

END PACKET basic storage;

PACKET basic identify DEFINES                 (* Autor: Heiko Indenbirken *)
                                              (* Stand: 20.08.1987/rr/mo  *)
                           identify,
                           convert paramfield,
                           dump ftn,
                           is basic function:            (* mo *)

LET nil = "";

LET ENTRY = STRUCT (TEXT param, INT no, next, OPN opn, DTYPE result);

ROW 256 ENTRY VAR ftn table;

clear ftn table;
init ftn names;
init int operator;
init real operator;
init text operator;
init predefined funktions;

PROC dump ftn (INT CONST n, TEXT VAR param, INT VAR no, next,
               OPN VAR opn, DTYPE VAR result):
 param  := ftn table [n].param;
 no     := ftn table [n].no;
 next   := ftn table [n].next;
 opn    := ftn table [n].opn;
 result := ftn table [n].result

END PROC dump ftn;

PROC identify (INT CONST ftn no, first, params, OPN VAR operation, BOOL VAR found):
  TEXT VAR param;
  INT VAR pos :: min (ftn no, 256);
  convert paramfield (first, params, param);
  REP IF param = ftn table [pos].param  AND ftn no = ftn table [pos].no
      THEN declare (params+1, ftn table [pos].result);
           declare (params+1, 1);
           operation := ftn table [pos].opn;
           found     := TRUE;
           LEAVE identify
      ELSE pos := ftn table [pos].next FI
  UNTIL pos <= 0 PER;                                           (* F14/rr *)
  operation := nop;
  found     := FALSE  .

END PROC identify;

PROC next free entry (INT VAR free pos):
  FOR free pos FROM 1 UPTO 256
  REP IF ftn table [free pos].next < 0 AND ftn table [free pos].no = 0  (* mo *)
    THEN LEAVE next free entry FI
  PER;
  errorstop ("Überlauf der Funktionstabelle")  .

END PROC next free entry;

PROC convert paramfield (INT CONST first, params, TEXT VAR param):
  INT VAR i;
  param := nil;
  FOR i FROM first UPTO params
  REP param CAT datatype PER  .

datatype:
  DTYPE CONST data :: dtype (i);
  IF data = int type
  THEN "I"
  ELIF data = real type
  THEN "R"
  ELIF data = text type
  THEN "T"
  ELIF data = bool type
  THEN "b"
  ELSE errorstop ("Falscher DTYPE: " + dump (data));
       nil
  FI  .

END PROC convert paramfield;

PROC convert paramfield (TEXT CONST params, INT CONST first):
  INT VAR i;
  FOR i FROM first UPTO first+length (params)-1
  REP parameter (i, this type, 1, GLOB 0) PER  .

this type:
  IF (params SUB i) = "I"
  THEN int type
  ELIF (params SUB i) = "R"
  THEN real type
  ELIF (params SUB i) = "T"
  THEN text type
  ELSE errorstop ("Unbekannter Typ: " + params);
       undefined type
  FI  .

END PROC convert paramfield;

PROC init op (INT CONST ftn no, TEXT CONST param, ftn name):
  IF elan opn found
  THEN insert new opn in chain
  ELSE errorstop ("PROC " + ftn name + " (" + param + ") nicht gefunden") FI  .

elan opn found:
  OPN VAR opn;
  BOOL VAR found;
  convert paramfield (param, 1);
  identify (ftn name, 1, length (param), opn, found);
  found  .

insert new opn in chain:
  INT VAR ftn pos :: ftn no;
  REP IF end of chain found
      THEN cat new entry in chain
      ELIF free entry in chain found
      THEN cover this entry
      ELSE next entry FI
  UNTIL ftn pos <= 0 PER  .

end of chain found:
  act entry.next = 0  .

cat new entry in chain:
  INT VAR free pos;
  next free entry (free pos);
  act entry.next := free pos;
  free entry := ENTRY:(param, ftn no, 0, opn, dtype (LENGTH param+1));
  LEAVE insert new opn in chain  .

free entry in chain found:
  act entry.next = -1 .

cover this entry:
  act entry := ENTRY:(param, ftn no, 0, opn, dtype (LENGTH param+1));
  LEAVE insert new opn in chain  .

next entry:
  ftn pos := act entry.next  .

act entry: ftn table [ftn pos]  .
free entry: ftn table [free pos]  .

END PROC init op;

BOOL PROC is basic function (INT CONST ftn no):         (* mo *)

  pos (ftn names, code (ftn no)) <> 0

END PROC is basic function;

.
clear ftn table:
  INT VAR k;
  FOR k FROM 1 UPTO 256
  REP ftn table [k] := ENTRY:(nil, 0,-1, nop, undefined type) PER  .

init ftn names:
  TEXT CONST ftn names :: "+-*/\^<=>"28""29""30""249""251""252""253""254"" +
                          ""128""130""131""134""136""137""141""143""142"" +
                          ""153""154""155""157""159""161""166""168""170""171""172"" +
                          ""174""175""178""179""182""184""183""187""192"" +
                          ""201""202""204""205""206""207""208""211""212"" +
                          ""215""221""228""229""230""231""232""233"";
  FOR k FROM 1 UPTO length (ftn names)
  REP ftn table [ftn pos] := ENTRY:(nil, ftn pos,-1, nop, void type) PER  .

ftn pos:
  code (ftn names SUB k)  .

init int operator:
  init op ( 43, "II", "+");
  init op ( 45, "II", "-");
  init op ( 42, "II", "*");
  init op ( 47, "II", "/");                 (* mo *)
  init op ( 92, "II", "DIV");               (* mo *)
  init op ( 94, "II", "^");
  init op ( 61, "II", "EQU");
  init op ( 29, "II", "UEQ");
  init op ( 60, "II", "LES");
  init op ( 28, "II", "LEQ");
  init op ( 62, "II", "GRE");
  init op ( 30, "II", "GEQ");
  init op (249, "II", "MOD");               (* mo *)
  init op (251, "II", "AND");
  init op (252, "II", "OR");
  init op (253, "II", "XOR");
  init op (254, "II", "EQV");
  init op (255, "II", "IMP").

init real operator:
  init op ( 43, "RR", "+");
  init op ( 45, "RR", "-");
  init op ( 42, "RR", "*");
  init op ( 47, "RR", "/");
  init op ( 92, "RR", "DIV");              (* mo *)
  init op ( 94, "RR", "^");
  init op ( 61, "RR", "EQU");
  init op ( 29, "RR", "UEQ");
  init op ( 60, "RR", "LES");
  init op ( 28, "RR", "LEQ");
  init op ( 62, "RR", "GRE");
  init op ( 30, "RR", "GEQ");
  init op (249, "RR", "realmod").          (* mo *)

init text operator:
  init op ( 43, "TT", "+");
  init op ( 61, "TT", "EQU");
  init op ( 29, "TT", "UEQ");
  init op ( 60, "TT", "LES");
  init op ( 28, "TT", "LEQ");
  init op ( 62, "TT", "GRE");
  init op ( 30, "TT", "GEQ")  .

init predefined funktions:
  init op (128, "I", "abs");
  init op (128, "R", "abs");
  init op (130, "T", "asc");
  init op (131, "R", "arctan");
  init op (131, "I", "arctan");
  init op (134, "I", "cdbl");
  init op (134, "R", "cdbl");
  init op (136, "I", "chr");
  init op (136, "R", "chr");
  init op (137, "R", "cint");
  init op (137, "I", "cint");
  init op (141, "R", "cos");
  init op (141, "I", "cos");
  init op (143, "T", "cvi");
  init op (142, "T", "cvd");
# init op (153, "", "eof");#                                     (* File *)
  init op (154, "", "errorline");
  init op (155, "", "errorcode");
  init op (157, "R", "exp");
  init op (157, "I", "exp");
  init op (159, "R", "floor");
  init op (159, "I", "floor");
  init op (161, "I", "fre");
  init op (161, "R", "fre");
  init op (161, "T", "fre");
  init op (166, "I", "hex");
  init op (166, "R", "hex");
  init op (168, "", "incharety");
  init op (170, "I", "inchars");
  init op (170, "R", "inchars");
  init op (171, "TT", "instr");
  init op (171, "ITT", "instr");
  init op (171, "RTT", "instr");
  init op (172, "I", "ent");
  init op (172, "R", "ent");
  init op (174, "TI", "left");
  init op (174, "TR", "left");
  init op (175, "T", "length");
# init op (178, "I", "line no");#                                (* File *)
  init op (179, "R", "ln");
  init op (179, "I", "ln");
  init op (182, "TII", "mid");
  init op (182, "TI", "mid");
  init op (182, "TRR", "mid");
  init op (182, "TR", "mid");
  init op (183, "I", "mkd");
  init op (183, "R", "mkd");
  init op (187, "I", "oct");
  init op (187, "R", "oct");
  init op (192, "I", "pos");
  init op (192, "R", "pos");
  init op (201, "TI", "right");
  init op (201, "TR", "right");
  init op (202, "", "rnd");                                      (* F12/rr *)
  init op (202, "I", "rnd");
  init op (202, "R", "rnd");
  init op (204, "I", "sign");
  init op (204, "R", "sign");
  init op (205, "R", "sin");
  init op (205, "I", "sin");
  init op (206, "I", "space");
  init op (206, "R", "space");
  init op (207, "I", "space");
  init op (207, "R", "space");
  init op (208, "R", "sqrt");
  init op (208, "I", "sqrt");
  init op (211, "I", "basictext");
  init op (211, "R", "basictext");
  init op (212, "IT", "string");
  init op (212, "RT", "string");
  init op (212, "II", "string");
  init op (212, "RR", "string");
  init op (212, "RI", "string");
  init op (212, "IR", "string");
  init op (215, "R", "tan");
  init op (215, "I", "tan");
  init op (221, "T", "val");                                      (* F18/rr *)
  init op (228, "", "errormessage");
  init op (229, "", "csrlin");
  init op (230, "I", "lpos");
  init op (230, "R", "lpos");
  init op (231, "", "time");
  init op (232, "", "date");
  init op (233, "", "timer").

END PACKET basic identify;

PACKET basic data handling                          (* Autor: R. Ruland   *)
                                                    (* Stand: 23.10.87/mo *)
       DEFINES init data,       
               data line,       
               data, read,
               restore,
               next int,
               next real,
               next text:       

LET (*                     R e s u l t    T y p e n                      *) 
    stat code = 0,   stat char = ""0"",
    data code = 1,   data char = ""1"",
    text code = 2,   text char = ""2"",

    int  overflow  =  4,
    real overflow  =  6;

INT VAR type;
TEXT VAR data text :: "", number text;

PROC init data:

   data text := ""

END PROC init data;


PROC init data (TEXT VAR data, INT VAR data pos):

  data      := data text;
  data pos  := 1

END PROC init data;


PROC restore (TEXT CONST data, INT VAR data pos, INT CONST line no):

  INT CONST data length :: LENGTH data;
  data pos := 1;
  WHILE data pos < data length
  REP type := code (data SUB data pos);
      data pos INCR 1;
      SELECT type OF
         CASE stat code            : IF int value (data, data pos) >= line no
                                        THEN LEAVE restore FI
         CASE data code, text code : data pos INCR int value (data, data pos)
         OTHERWISE : errorstop (1051, "Fehlerhaften Dateneintrag gefunden: " + text (type))
      ENDSELECT;
  PER;
  errorstop (1004, "RESTORE: Keine DATA-Anweisung in oder nach Zeile " + text (line no)
                     + " gefunden");

END PROC restore;

 
INT PROC next int (TEXT CONST data, INT VAR data pos):

   number text := next text (data, data pos);
   disable stop;
   INT VAR result := int (number text);
   IF   is error
        THEN IF error code = int overflow THEN handle overflow FI;
   ELIF NOT last conversion ok CAND number text <> "" 
        THEN errorstop (1013, "READ: Falscher Datentyp, " + number text + " ist kein INT")
   FI;
   result

   . handle overflow :
       clear error;
       result := result value;
       IF cursor x pos <> 1 THEN next line FI;
       basic out ("WARNUNG : INT-Überlauf bei READ, gefunden: " + number text);
       next line;

       . result value :
           IF (number text SUB 1) = "-" THEN minint ELSE maxint FI

END PROC next int;

 
REAL PROC next real (TEXT CONST data, INT VAR data pos):

   number text := next text (data, data pos);
   disable stop;
   REAL VAR result := val (number text);
   IF   is error
        THEN IF error code = real overflow OR error code = int overflow  (* <- wegen Fehler in REAL PROC real (T C) *)
                THEN handle overflow or underflow
             FI;
   ELIF NOT last conversion ok CAND number text <> "" 
        THEN errorstop (1013, "READ: Falscher Datentyp, " + number text + " ist kein REAL")
   FI;
   result

   . handle overflow or underflow :                          (* F23/rr *) 
       clear error;
       IF cursor x pos <> 1 THEN next line FI;
       basic out ("WARNUNG : " + overflow or underflow + " bei READ, gefunden: " + number text);
       next line;

   . overflow or underflow :
       IF is overflow                            
          THEN result := sign * (max real - 0.99999999999994e120); (* <- wegen Fehler in TEXT PROC text (R C) *)
               "REAL-Überlauf"
          ELSE result := 0.0;
               "REAL-Unterlauf"
       FI

       . sign :
           IF (number text SUB 1) = "-" THEN -1.0 ELSE 1.0 FI

       . is overflow :
           INT VAR exponent pos := pos (number text, "E"); 
           IF exponent pos = 0 THEN exponent pos := pos (number text, "e") FI;
           IF exponent pos = 0
              THEN TRUE
              ELSE (number text SUB (exponent pos + 1)) <> "-"
           FI

END PROC next real;


TEXT PROC next text (TEXT CONST data, INT VAR data pos):

   INT CONST len :: int value (data, data pos);
   data pos INCR len;
   subtext (data, data pos-len, data pos-1)

END PROC next text;


INT PROC int value (TEXT CONST data, INT VAR data pos):

   data pos INCR 2;
   subtext (data, data pos-2, data pos-1) ISUB 1

END PROC int value;
 

PROC data line (INT CONST line no):

  data text CAT stat char;
  data text CAT mki (line no)

END PROC data line;


PROC data (TEXT CONST string, DTYPE VAR data type) :

  data text CAT data + mki (length (string));
  data text CAT string;

  . data :
      IF   data type = void type
           THEN data char
      ELIF data type = text type
           THEN text char
           ELSE errorstop (1051, "Unbekannter DTYPE: " + dump (data type)); ""
      FI

END PROC data;


PROC read (TEXT CONST data, INT VAR data pos, INT VAR i):

  type := code (data SUB data pos);
  data pos INCR 1;
  IF   data pos >= LENGTH data
       THEN errorstop (1004, "Keine Daten mehr für READ")
  ELIF type = data code
       THEN i := next int (data, data pos)
  ELIF type = stat code
       THEN data pos INCR 2;
            read (data, data pos, i)
       ELSE errorstop (1013, "READ: Falscher Datentyp, " + data string (data,data pos) + " ist kein INT")
  FI;

END PROC read;


PROC read (TEXT CONST data, INT VAR data pos, REAL VAR r):

  type := code (data SUB data pos);
  data pos INCR 1;
  IF   data pos >= LENGTH data
       THEN errorstop (1004, "Keine Daten mehr für READ")
  ELIF type = data code
       THEN r := next real (data, data pos)
  ELIF type = stat code
       THEN data pos INCR 2;
            read (data, data pos, r)
       ELSE errorstop (1013, "READ: Falscher Datentyp, " + data string (data,data pos) + " ist kein REAL")
  FI;

END PROC read;


PROC read (TEXT CONST data, INT VAR data pos, TEXT VAR t):

  type := code (data SUB data pos);
  data pos INCR 1;
  IF   data pos >= LENGTH data
       THEN errorstop (1004, "Keine Daten mehr für READ")
  ELIF type = data code OR type = text code
       THEN t := next text (data, data pos)
  ELIF type = stat code
       THEN data pos INCR 2;
            read (data, data pos, t)
       ELSE errorstop (1013, "READ: Falscher Datentyp, " + data string (data,data pos) + " ist kein TEXT")
  FI;

END PROC read;
 

TEXT PROC data string (TEXT CONST data, INT VAR data pos):

  IF type = text code
     THEN """" + next text (data, data pos) + """"
     ELSE "unbekannter DTYPE: " + text (type)
  FI

END PROC data string;

END PACKET basic data handling;


PACKET basic odds and ends DEFINES trace,       (* Autor: Heiko Indenbirken *)
                                   start basic, (* Stand: 26.10.1987/rr/mo  *)
                                   end basic,
                                   loop end,
                                   basic stop:

(*                            Fehlerbehandlung                           *)

PROC trace (INT CONST stat no):
  basic out ("[" + text (stat no) + "]")

END PROC trace;

(*Laufzeitprozeduren                                                     *)
PROC start basic:
  set line nr (0);
  initialize random (0.1);                                   (* F26/rr *)
  init output;
  init input

END PROC start basic;

PROC end basic:
  IF is error
    THEN switch back to old sysout state
  FI  .

END PROC end basic; 

(*                          Schleifenüberprüfung                         *)
BOOL PROC loop end (REAL CONST x, max, step) :
  IF step > 0.0
  THEN x > max
  ELSE x < max FI

END PROC loop end;

BOOL PROC loop end (INT CONST x, max, step) :
  IF step > 0
  THEN x > max
  ELSE x < max FI

END PROC loop end;

PROC basic stop (INT CONST stat no):
  basic out ("STOP beendet das Programm in Zeile " + text (stat no));
  next line

END PROC basic stop;

END PACKET basic odds and ends