MODULE Strings;
(**
project = "BlackBox"
organization = "www.oberon.ch"
contributors = "Oberon microsystems"
version = "System/Rsrc/About"
copyright = "System/Rsrc/About"
license = "Docu/BB-License"
changes = ""
issues = ""
**)
IMPORT Math;
CONST
charCode* = -1; decimal* = 10; hexadecimal* = -2; roman*= -3;
digitspace* = 08FX;
showBase* = TRUE; hideBase* = FALSE;
minLongIntRev = "8085774586302733229"; (* reversed string of -MIN(LONGINT) *)
VAR
maxExp: INTEGER;
maxDig: INTEGER;
factor: REAL; (* 10^maxDig *)
digits: ARRAY 17 OF CHAR;
toUpper, toLower: ARRAY 256 OF CHAR;
(* integer conversions *)
PROCEDURE IntToString* (x: LONGINT; OUT s: ARRAY OF CHAR);
VAR j, k: INTEGER; ch: CHAR; a: ARRAY 32 OF CHAR;
BEGIN
IF x # MIN(LONGINT) THEN
IF x < 0 THEN s[0] := "-"; k := 1; x := -x ELSE k := 0 END;
j := 0; REPEAT a[j] := CHR(x MOD 10 + ORD("0")); x := x DIV 10; INC(j) UNTIL x = 0
ELSE
a := minLongIntRev; s[0] := "-"; k := 1;
j := 0; WHILE a[j] # 0X DO INC(j) END
END;
ASSERT(k + j < LEN(s), 23);
REPEAT DEC(j); ch := a[j]; s[k] := ch; INC(k) UNTIL j = 0;
s[k] := 0X
END IntToString;
PROCEDURE IntToStringForm* (x: LONGINT; form, minWidth: INTEGER; fillCh: CHAR;
showBase: BOOLEAN; OUT s: ARRAY OF CHAR);
VAR base, i, j, k, si: INTEGER; mSign: BOOLEAN; a: ARRAY 128 OF CHAR; c1, c5, c10: CHAR;
BEGIN
ASSERT((form = charCode) OR (form = hexadecimal) OR (form = roman) OR ((form >= 2) & (form <= 16)), 20);
ASSERT(minWidth >= 0, 22);
IF form = charCode THEN base := 16
ELSIF form = hexadecimal THEN base := 16
ELSE base := form
END;
IF form = roman THEN
ASSERT((x > 0) & (x < 3999), 21);
base := 1000; i := 0; mSign := FALSE;
WHILE (base > 0) & (x > 0) DO
IF base = 1 THEN c1 := "I"; c5 := "V"; c10 := "X"
ELSIF base = 10 THEN c1 := "X"; c5 := "L"; c10 := "C"
ELSIF base = 100 THEN c1 := "C"; c5 := "D"; c10 := "M"
ELSE c1 := "M"
END;
k := SHORT(x DIV base); x := x MOD base;
IF k IN {4, 9} THEN a[i] := c1; INC(i) END;
IF k IN {4 .. 8} THEN a[i] := c5; INC(i) END;
IF k = 9 THEN a[i] := c10; INC(i)
ELSIF k IN {1 .. 3, 6 .. 8} THEN
j := k MOD 5;
REPEAT a[i] := c1; INC(i); DEC(j) UNTIL j = 0
END;
base := base DIV 10
END
ELSIF (form = hexadecimal) OR (form = charCode) THEN
i := 0; mSign := FALSE;
IF showBase THEN DEC(minWidth) END;
REPEAT
a[i] := digits[x MOD base]; x := x DIV base; INC(i)
UNTIL (x = 0) OR (x = -1) OR (i = LEN(a));
IF x = -1 THEN fillCh := "F" END
ELSE
IF x < 0 THEN
i := 0; mSign := TRUE; DEC(minWidth);
REPEAT
IF x MOD base = 0 THEN
a[i] := digits[0]; x := x DIV base
ELSE
a[i] := digits[base - x MOD base]; x := x DIV base + 1
END;
INC(i)
UNTIL (x = 0) OR (i = LEN(a))
ELSE
i := 0; mSign := FALSE;
REPEAT
a[i] := digits[x MOD base]; x := x DIV base; INC(i)
UNTIL (x = 0) OR (i = LEN(a))
END;
IF showBase THEN DEC(minWidth);
IF base < 10 THEN DEC(minWidth) ELSE DEC(minWidth,2) END
END
END;
si := 0;
IF mSign & (fillCh = "0") & (si < LEN(s)) THEN s[si] := "-"; INC(si); mSign := FALSE END;
WHILE minWidth > i DO
IF si < LEN(s) THEN s[si] := fillCh; INC(si) END;
DEC(minWidth)
END;
IF mSign & (si < LEN(s)) THEN s[si] := "-"; INC(si) END;
IF form = roman THEN
j := 0;
WHILE j < i DO
IF si < LEN(s) THEN s[si] := a[j]; INC(si) END;
INC(j)
END
ELSE
REPEAT DEC(i);
IF si < LEN(s) THEN s[si] := a[i]; INC(si) END
UNTIL i = 0
END;
IF showBase & (form # roman) THEN
IF (form = charCode) & (si < LEN(s)) THEN s[si] := "X"; INC(si)
ELSIF (form = hexadecimal) & (si < LEN(s)) THEN s[si] := "H"; INC(si)
ELSIF (form < 10) & (si < LEN(s)-1) THEN s[si] := "%"; s[si+1] := digits[base]; INC(si, 2)
ELSIF (si < LEN(s) - 2) THEN
s[si] := "%"; s[si+1] := digits[base DIV 10]; s[si+2] := digits[base MOD 10]; INC(si, 3)
END
END;
IF si < LEN(s) THEN s[si] := 0X ELSE HALT(23) END
END IntToStringForm;
PROCEDURE StringToInt* (IN s: ARRAY OF CHAR; OUT x: INTEGER; OUT res: INTEGER);
CONST hexLimit = MAX(INTEGER) DIV 8 + 1;
VAR i, j, k, digits: INTEGER; ch, top: CHAR; neg: BOOLEAN; base: INTEGER;
BEGIN
res := 0; i := 0; ch := s[0];
WHILE (ch # 0X) & (ch <= " ") OR (ch = 8BX) OR (ch = 8FX) OR (ch = 0A0X) DO (* ignore leading blanks *)
INC(i); ch := s[i]
END;
j := i; top := "0";
WHILE (ch # 0X) & (ch # "H") & (ch # "X") & (ch # "%") DO
IF ch > top THEN top := ch END;
INC(j); ch := s[j]
END;
IF (ch = "H") OR (ch = "X") THEN
x := 0; ch := s[i];
IF ("0" <= ch) & (ch <= "9") OR ("A" <= ch) & (ch <= "F") THEN
WHILE ch = "0" DO INC(i); ch := s[i] END;
digits := 0;
WHILE (res = 0) & (("0" <= ch) & (ch <= "9") OR ("A" <= ch) & (ch <= "F")) DO
IF ch < "A" THEN k := ORD(ch) - ORD("0")
ELSE k := ORD(ch) - ORD("A") + 10
END;
IF digits < 8 THEN
x := x MOD hexLimit;
IF x >= hexLimit DIV 2 THEN x := x - hexLimit END;
x := x * 16 + k; INC(i); ch := s[i]
ELSE res := 1
END;
INC(digits)
END;
IF res = 0 THEN
IF (ch # "H") & (ch # "X") OR (s[i+1] # 0X) THEN res := 2 END
END
ELSE res := 2
END
ELSE
IF ch = "%" THEN
INC(j); ch := s[j]; base := 0;
IF ("0" <= ch) & (ch <= "9") THEN
k := ORD(ch) - ORD("0");
REPEAT
base := base * 10 + k;
INC(j); ch := s[j]; k := ORD(ch) - ORD("0")
UNTIL (ch < "0") OR (ch > "9") OR (base > (MAX(INTEGER) - k) DIV 10);
IF ("0" <= ch) & (ch <= "9") THEN base := 0 END
END
ELSE
base := 10
END;
IF (base < 2) OR (base > 16) THEN
res := 2
ELSIF (base <= 10) & (ORD(top) < base + ORD("0"))
OR (base > 10) & (ORD(top) < base - 10 + ORD("A")) THEN
x := 0; ch := s[i]; neg := FALSE;
IF ch = "-" THEN INC(i); ch := s[i]; neg := TRUE ELSIF ch = "+" THEN INC(i); ch := s[i] END;
WHILE (ch # 0X) & (ch <= " ") DO INC(i); ch := s[i] END;
IF ("0" <= ch) & (ch <= "9") OR ("A" <= ch) & (ch <= "F") THEN
IF ch <= "9" THEN k := ORD(ch) - ORD("0") ELSE k := ORD(ch) - ORD("A") + 10 END;
WHILE (("0" <= ch) & (ch <= "9") OR ("A" <= ch) & (ch <= "F")) & (res = 0) DO
IF x >= (MIN(INTEGER) + (base - 1) + k) DIV base THEN
x := x * base - k; INC(i); ch := s[i];
IF ch <= "9" THEN k := ORD(ch) - ORD("0") ELSE k := ORD(ch) - ORD("A") + 10 END
ELSE res := 1
END
END
ELSE res := 2
END;
IF res = 0 THEN
IF ~neg THEN
IF x > MIN(INTEGER) THEN x := -x ELSE res := 1 END
END;
IF (ch # 0X) & (ch # "%") THEN res := 2 END
END
ELSE
res := 2
END
END
END StringToInt;
PROCEDURE StringToLInt* (IN s: ARRAY OF CHAR; OUT x: LONGINT; OUT res: INTEGER);
CONST hexLimit = MAX(LONGINT) DIV 8 + 1;
VAR i, j, k, digits: INTEGER; ch, top: CHAR; neg: BOOLEAN; base: INTEGER;
BEGIN
res := 0; i := 0; ch := s[0];
WHILE (ch # 0X) & (ch <= " ") OR (ch = 8BX) OR (ch = 8FX) OR (ch = 0A0X) DO (* ignore leading blanks *)
INC(i); ch := s[i]
END;
j := i; top := "0";
WHILE (ch # 0X) & (ch # "H") & (ch # "X") & (ch # "%") DO
IF ch > top THEN top := ch END;
INC(j); ch := s[j]
END;
IF (ch = "H") OR (ch = "X") THEN
x := 0; ch := s[i];
IF ("0" <= ch) & (ch <= "9") OR ("A" <= ch) & (ch <= "F") THEN
WHILE ch = "0" DO INC(i); ch := s[i] END;
digits := 0;
WHILE (res = 0) & (("0" <= ch) & (ch <= "9") OR ("A" <= ch) & (ch <= "F")) DO
IF ch < "A" THEN k := ORD(ch) - ORD("0")
ELSE k := ORD(ch) - ORD("A") + 10
END;
IF digits < 16 THEN
x := x MOD hexLimit;
IF x >= hexLimit DIV 2 THEN x := x - hexLimit END;
x := x * 16 + k; INC(i); ch := s[i]
ELSE res := 1
END;
INC(digits)
END;
IF res = 0 THEN
IF (ch # "H") & (ch # "X") OR (s[i+1] # 0X) THEN res := 2 END
END
ELSE res := 2
END
ELSE
IF ch = "%" THEN
INC(j); ch := s[j]; base := 0;
IF ("0" <= ch) & (ch <= "9") THEN
k := ORD(ch) - ORD("0");
REPEAT
base := base * 10 + k;
INC(j); ch := s[j]; k := ORD(ch) - ORD("0")
UNTIL (ch < "0") OR (ch > "9") OR (base > (MAX(INTEGER) - k) DIV 10);
IF ("0" <= ch) & (ch <= "9") THEN base := 0 END
END
ELSE
base := 10
END;
IF (base < 2) OR (base > 16) THEN
res := 2
ELSIF (base <= 10) & (ORD(top) < base + ORD("0"))
OR (base > 10) & (ORD(top) < base -10 + ORD("A")) THEN
x := 0; ch := s[i]; neg := FALSE;
IF ch = "-" THEN INC(i); ch := s[i]; neg := TRUE ELSIF ch = "+" THEN INC(i); ch := s[i] END;
WHILE (ch # 0X) & (ch <= " ") DO INC(i); ch := s[i] END;
IF ("0" <= ch) & (ch <= "9") OR ("A" <= ch) & (ch <= "F") THEN
IF ch <= "9" THEN k := ORD(ch) - ORD("0") ELSE k := ORD(ch) - ORD("A") + 10 END;
WHILE (("0" <= ch) & (ch <= "9") OR ("A" <= ch) & (ch <= "F")) & (res = 0) DO
IF x >= (MIN(LONGINT) + (base - 1) + k) DIV base THEN
x := x * base - k; INC(i); ch := s[i];
IF ch <= "9" THEN k := ORD(ch) - ORD("0") ELSE k := ORD(ch) - ORD("A") + 10 END
ELSE res := 1
END
END
ELSE res := 2
END;
IF res = 0 THEN
IF ~neg THEN
IF x > MIN(LONGINT) THEN x := -x ELSE res := 1 END
END;
IF (ch # 0X) & (ch # "%") THEN res := 2 END
END
ELSE
res := 2
END
END
END StringToLInt;
(* real conversions *)
PROCEDURE RealToStringForm* (x: REAL; precision, minW, expW: INTEGER; fillCh: CHAR;
OUT s: ARRAY OF CHAR);
VAR exp, len, i, j, n, k, p: INTEGER; m: ARRAY 80 OF CHAR; neg: BOOLEAN;
BEGIN
ASSERT((precision > 0) (*& (precision <= 18)*), 20);
ASSERT((minW >= 0) & (minW < LEN(s)), 21);
ASSERT((expW > -LEN(s)) & (expW <= 3), 22);
exp := Math.Exponent(x);
IF exp = MAX(INTEGER) THEN
IF fillCh = "0" THEN fillCh := digitspace END;
x := Math.Mantissa(x);
IF x = -1 THEN m := "-inf"; n := 4
ELSIF x = 1 THEN m := "inf"; n := 3
ELSE m := "nan"; n := 3
END;
i := 0; j := 0;
WHILE minW > n DO s[i] := fillCh; INC(i); DEC(minW) END;
WHILE (j <= n) & (i < LEN(s)) DO s[i] := m[j]; INC(i); INC(j) END
ELSE
neg := FALSE; len := 1; m := "00";
IF x < 0 THEN x := -x; neg := TRUE; DEC(minW) END;
IF x # 0 THEN
exp := (exp - 8) * 30103 DIV 100000; (* * log(2) *)
IF exp > 0 THEN
n := SHORT(ENTIER(x / Math.IntPower(10, exp)));
x := x / Math.IntPower(10, exp) - n
ELSIF exp > -maxExp THEN
n := SHORT(ENTIER(x * Math.IntPower(10, -exp)));
x := x * Math.IntPower(10, -exp) - n
ELSE
n := SHORT(ENTIER(x * Math.IntPower(10, -exp - 2 * maxDig) * factor * factor));
x := x * Math.IntPower(10, -exp - 2 * maxDig) * factor * factor - n
END;
(* x0 = (n + x) * 10^exp, 200 < n < 5000 *)
p := precision - 4;
IF n < 1000 THEN INC(p) END;
IF (expW < 0) & (p > exp - expW) THEN p := exp - expW END;
IF p >= 0 THEN
x := x + 0.5 / Math.IntPower(10, p); (* rounding correction *)
IF x >= 1 THEN INC(n); x := x - 1 END
ELSIF p = -1 THEN INC(n, 5)
ELSIF p = -2 THEN INC(n, 50)
ELSIF p = -3 THEN INC(n, 500)
END;
i := 0; k := 1000; INC(exp, 3);
IF n < 1000 THEN k := 100; DEC(exp) END;
WHILE (i < precision) & ((k > 0) OR (x # 0)) DO
IF k > 0 THEN p := n DIV k; n := n MOD k; k := k DIV 10
ELSE x := x * 10; p := SHORT(ENTIER(x)); x := x - p
END;
m[i] := CHR(p + ORD("0")); INC(i);
IF p # 0 THEN len := i END
END
END;
(* x0 = m[0].m[1]...m[len-1] * 10^exp *)
i := 0;
IF (expW < 0) OR (expW = 0) & (exp >= -3) & (exp <= len + 1) THEN
n := exp + 1; k := len - n;
IF n < 1 THEN n := 1 END;
IF expW < 0 THEN k := -expW ELSIF k < 1 THEN k := 1 END;
j := minW - n - k - 1; p := -exp;
IF neg & (p >= MAX(0, n) + MAX(0, k)) THEN neg := FALSE; INC(j) END
ELSE
IF ABS(exp) >= 100 THEN expW := 3
ELSIF (expW < 2) & (ABS(exp) >= 10) THEN expW := 2
ELSIF expW < 1 THEN expW := 1
END;
IF len < 2 THEN len := 2 END;
j := minW - len - 3 - expW; k := len;
IF j > 0 THEN
k := k + j; j := 0;
IF k > precision THEN j := k - precision; k := precision END
END;
n := 1; DEC(k); p := 0
END;
IF neg & (fillCh = "0") THEN s[i] := "-"; INC(i); neg := FALSE END;
WHILE j > 0 DO s[i] := fillCh; INC(i); DEC(j) END;
IF neg & (i < LEN(s)) THEN s[i] := "-"; INC(i) END;
j := 0;
WHILE (n > 0) & (i < LEN(s)) DO
IF (p <= 0) & (j < len) THEN s[i] := m[j]; INC(j) ELSE s[i] := "0" END;
INC(i); DEC(n); DEC(p)
END;
IF i < LEN(s) THEN s[i] := "."; INC(i) END;
WHILE (k > 0) & (i < LEN(s)) DO
IF (p <= 0) & (j < len) THEN s[i] := m[j]; INC(j) ELSE s[i] := "0" END;
INC(i); DEC(k); DEC(p)
END;
IF expW > 0 THEN
IF i < LEN(s) THEN s[i] := "E"; INC(i) END;
IF i < LEN(s) THEN
IF exp < 0 THEN s[i] := "-"; exp := -exp ELSE s[i] := "+" END;
INC(i)
END;
IF (expW = 3) & (i < LEN(s)) THEN s[i] := CHR(exp DIV 100 + ORD("0")); INC(i) END;
IF (expW >= 2) & (i < LEN(s)) THEN s[i] := CHR(exp DIV 10 MOD 10 + ORD("0")); INC(i) END;
IF i < LEN(s) THEN s[i] := CHR(exp MOD 10 + ORD("0")); INC(i) END
END
END;
IF i < LEN(s) THEN s[i] := 0X ELSE HALT(23) END
END RealToStringForm;
PROCEDURE RealToString* (x: REAL; OUT s: ARRAY OF CHAR);
BEGIN
RealToStringForm(x, 16, 0, 0, digitspace, s)
END RealToString;
PROCEDURE StringToReal* (IN s: ARRAY OF CHAR; OUT x: REAL; OUT res: INTEGER);
VAR first, last, point, e, n, i, exp: INTEGER; y: REAL; ch: CHAR; neg, negExp, dig: BOOLEAN;
BEGIN
res := 0; i := 0; ch := s[0]; dig := FALSE;
WHILE (ch # 0X) & (ch <= " ") OR (ch = 8BX) OR (ch = 8FX) OR (ch = 0A0X) DO INC(i); ch := s[i] END;
IF ch = "+" THEN
neg := FALSE; INC(i); ch := s[i]
ELSIF ch = "-" THEN
neg := TRUE; INC(i); ch := s[i]
ELSE
neg := FALSE
END;
WHILE ch = "0" DO INC(i); ch := s[i]; dig := TRUE END;
first := i; e := 0;
WHILE ("0" <= ch) & (ch <= "9") DO INC(i); ch := s[i]; INC(e); dig := TRUE END;
point := i;
IF ch = "." THEN
INC(i); ch := s[i];
IF e = 0 THEN
WHILE ch = "0" DO INC(i); ch := s[i]; DEC(e); dig := TRUE END;
first := i
END;
WHILE ("0" <= ch) & (ch <= "9") DO INC(i); ch := s[i]; dig := TRUE END
END;
last := i - 1; exp := 0;
IF (ch = "E") OR (ch = "D") THEN
INC(i); ch := s[i]; negExp := FALSE;
IF ch = "-" THEN negExp := TRUE; INC(i); ch := s[i]
ELSIF ch = "+" THEN INC(i); ch := s[i]
END;
WHILE ("0" <= ch) & (ch <= "9") & (exp < 1000) DO
exp := exp * 10 + (ORD(ch) - ORD("0"));
INC(i); ch := s[i]
END;
IF negExp THEN exp := -exp END
END;
exp := exp + e; x := 0; y := 0; n := 0;
WHILE (n < maxDig) & (first <= last) DO
IF first # point THEN x := x * 10 + (ORD(s[first]) - ORD("0")); INC(n) END;
INC(first)
END;
WHILE last >= first DO
IF last # point THEN y := (y + (ORD(s[last]) - ORD("0"))) / 10 END;
DEC(last)
END;
IF ~dig OR (ch # 0X) THEN res := 2 (* syntax error *)
ELSIF exp < -maxExp - maxDig THEN
x := 0.0
ELSIF exp < -maxExp + maxDig THEN
x := (x + y) / Math.IntPower(10, n - exp - 2 * maxDig) / factor / factor
ELSIF exp < n THEN
x := (x + y) / Math.IntPower(10, n - exp)
ELSIF exp < maxExp THEN
x := (x + y) * Math.IntPower(10, exp - n)
ELSIF exp = maxExp THEN
x := (x + y) * (Math.IntPower(10, exp - n) / 16);
IF x <= MAX(REAL) / 16 THEN x := x * 16
ELSE res := 1 (* overflow *)
END
ELSE res := 1 (* overflow *)
END;
IF neg THEN x := -x END
END StringToReal;
(* ----------------------------- string manipulation routines --------------------------- *)
PROCEDURE Valid* (IN s: ARRAY OF CHAR): BOOLEAN;
VAR i: INTEGER;
BEGIN i := 0;
WHILE (i < LEN(s)) & (s[i] # 0X) DO INC(i) END;
RETURN i < LEN(s)
END Valid;
PROCEDURE Upper* (ch: CHAR): CHAR;
BEGIN
IF ORD(ch) < 256 THEN RETURN toUpper[ORD(ch)] ELSE RETURN ch END
END Upper;
PROCEDURE ToUpper* (in: ARRAY OF CHAR; OUT out: ARRAY OF CHAR);
VAR i, max: INTEGER;
BEGIN i := 0; max := LEN(out)-1;
WHILE (in[i] # 0X) & (i < max) DO
IF ORD(in[i]) < 256 THEN out[i] := toUpper[ORD(in[i])] ELSE out[i] := in[i] END;
INC(i)
END;
out[i] := 0X
END ToUpper;
PROCEDURE Lower* (ch: CHAR): CHAR;
BEGIN
IF ORD(ch) < 256 THEN RETURN toLower[ORD(ch)] ELSE RETURN ch END
END Lower;
PROCEDURE ToLower* (in: ARRAY OF CHAR; OUT out: ARRAY OF CHAR);
VAR i, max: INTEGER;
BEGIN i := 0; max := LEN(out)-1;
WHILE (in[i] # 0X) & (i < max) DO
IF ORD(in[i]) < 256 THEN out[i] := toLower[ORD(in[i])] ELSE out[i] := in[i] END;
INC(i)
END;
out[i] := 0X
END ToLower;
PROCEDURE Replace* (VAR s: ARRAY OF CHAR; pos, len: INTEGER; IN rep: ARRAY OF CHAR);
(* replace stretch s[pos]..s[pos+len-1] with rep *)
(* insert semantics if len = 0; delete semantics if Len(rep) = 0 *)
VAR i, j, k, max, lenS: INTEGER; ch: CHAR;
BEGIN
ASSERT(len >= 0, 20); ASSERT(pos >= 0, 21);
lenS := LEN(s$); max := LEN(s) - 1;
IF pos <= lenS THEN i := pos; j := 0;
IF pos+len > lenS THEN len := lenS - pos END;
WHILE (rep[j] # 0X) & (len > 0) DO
s[i] := rep[j]; INC(i); INC(j); DEC(len)
END;
IF len > 0 THEN (* delete the remaining part of the stretch [pos, pos+len) *)
REPEAT ch := s[i+len]; s[i] := ch; INC(i) UNTIL ch = 0X
ELSE (* insert the remaining part of rep *)
len := LEN(rep$) - j; k := lenS + len;
IF k > max THEN k := max END;
s[k] := 0X;
WHILE k - len >= i DO s[k] := s[k-len]; DEC(k) END;
WHILE (rep[j] # 0X) & (i < max) DO s[i] := rep[j]; INC(i); INC(j) END
END
END
END Replace;
PROCEDURE Extract* (s: ARRAY OF CHAR; pos, len: INTEGER; OUT res: ARRAY OF CHAR);
VAR i, j, max: INTEGER;
BEGIN
ASSERT(len >= 0, 20); ASSERT(pos >= 0, 21);
i := 0; j := 0; max := LEN(res) - 1;
WHILE (i < pos) & (s[i] # 0X) DO INC(i) END;
WHILE (j < len) & (j < max) & (s[i] # 0X) DO res[j] := s[i]; INC(j); INC(i) END;
res[j] := 0X
END Extract;
PROCEDURE Find* (IN s: ARRAY OF CHAR; IN pat: ARRAY OF CHAR; start: INTEGER; OUT pos: INTEGER);
VAR j: INTEGER;
BEGIN
ASSERT(start >= 0, 20);
IF (start = 0) OR (start <= LEN(s$) - LEN(pat$)) THEN
(* start = 0 is optimization: need not call Len *)
pos := start;
WHILE s[pos] # 0X DO j := 0;
WHILE (s[pos+j] = pat[j]) & (pat[j] # 0X) DO INC(j) END;
IF pat[j] = 0X THEN RETURN END;
INC(pos)
END
END;
pos := -1 (* pattern not found *)
END Find;
PROCEDURE Init;
VAR i: INTEGER;
BEGIN
FOR i := 0 TO 255 DO toUpper[i] :=CHR(i); toLower[i] := CHR(i) END;
FOR i := ORD("A") TO ORD("Z") DO toLower[i] := CHR(i + 32); toUpper[i + 32] := CHR(i) END;
FOR i := ORD("À") TO ORD ("Ö") DO toLower[i] := CHR(i + 32); toUpper[i + 32] := CHR(i) END;
FOR i := ORD("Ø") TO ORD ("Þ") DO toLower[i] := CHR(i + 32); toUpper[i + 32] := CHR(i) END;
digits := "0123456789ABCDEF";
maxExp := SHORT(ENTIER(Math.Log(MAX(REAL)))) + 1;
maxDig := SHORT(ENTIER(-Math.Log(Math.Eps())));
factor := Math.IntPower(10, maxDig)
END Init;
BEGIN
Init
END Strings.