MODULE TextExtras;
*************************************************************************
Copyright (C) Olivetti 1989
All Rights reserved
Use and copy of this software and preparation of derivative works based
upon this software are permitted to any person, provided this same
copyright notice and the following Olivetti warranty disclaimer are
included in any copy of the software or any modification thereof or
derivative work therefrom made by any person.
This software is made available AS IS and Olivetti disclaims all
warranties with respect to this software, whether expressed or implied
under any law, including all implied warranties of merchantibility and
fitness for any purpose. In no event shall Olivetti be liable for any
damages whatsoever resulting from loss of use, data or profits or
otherwise arising out of or in connection with the use or performance
of this software.
*************************************************************************
IMPORT Text, Text8;
IMPORT ASCII;
PROCEDURE Compare(t, u: T): INTEGER RAISES {} =
VAR
minLength := Text.Length(t);
otherLength := Text.Length(u);
lengthDiff: INTEGER := minLength - otherLength;
i: CARDINAL := 0;
BEGIN
IF lengthDiff > 0 THEN minLength := otherLength END;
WHILE i < minLength DO
VAR
ti := ORD(Text.GetChar (t, i));
ui := ORD(Text.GetChar (u, i)); (* workaround compiler bug *)
BEGIN (* on byte subtractions *)
WITH diff = ti - ui DO
IF diff # 0 THEN RETURN diff ELSE INC(i) END;
END;
END;
END;
RETURN lengthDiff;
END Compare;
PROCEDURE CICompare(t, u: T): INTEGER RAISES {} =
VAR
minLength := Text.Length(t);
otherLength := Text.Length(u);
lengthDiff := minLength - otherLength;
i: CARDINAL := 0;
BEGIN
IF lengthDiff > 0 THEN minLength := otherLength END;
WHILE i < minLength DO
WITH diff = ORD(ASCII.Upper[Text.GetChar (t, i)]) - ORD(ASCII.Upper[Text.GetChar (u, i)]) DO
IF diff # 0 THEN RETURN diff ELSE INC(i) END;
END;
END;
RETURN lengthDiff;
END CICompare;
PROCEDURE CIEqual(t, u: T): BOOLEAN RAISES {} =
VAR
lt: CARDINAL := Text.Length(t);
lu: CARDINAL := Text.Length(u);
i: CARDINAL := 0;
BEGIN
IF lt = lu THEN
WHILE i<lt DO
IF ASCII.Upper[Text.GetChar (t, i)] # ASCII.Upper[Text.GetChar (u, i)] THEN
RETURN FALSE
ELSE INC(i)
END;
END;
RETURN TRUE;
ELSE RETURN FALSE
END;
END CIEqual;
EXCEPTION BadFind;
PROCEDURE FindChar(t: T; ch: CHAR; VAR index: CARDINAL): BOOLEAN RAISES {} =
VAR
i: CARDINAL := index;
lt: CARDINAL := Text.Length(t);
BEGIN
IF i >= lt THEN
IF i = lt THEN RETURN FALSE ELSE
<*FATAL BadFind *> BEGIN RAISE BadFind END;
END;
END;
REPEAT
IF Text.GetChar (t, i) = ch THEN index := i; RETURN TRUE END;
INC(i);
UNTIL i = lt;
index := i;
RETURN FALSE;
END FindChar;
PROCEDURE FindCharSet(
t: T;
READONLY charSet: ASCII.Set;
VAR index: CARDINAL)
: BOOLEAN
RAISES {} =
VAR
i: CARDINAL := index;
lt: CARDINAL := Text.Length(t);
BEGIN
IF i >= lt THEN
IF i = lt THEN RETURN FALSE ELSE
<*FATAL BadFind*> BEGIN RAISE BadFind END;
END
END;
REPEAT
IF Text.GetChar (t, i) IN charSet THEN index := i; RETURN TRUE END;
INC(i);
UNTIL i = lt;
index := i;
RETURN FALSE;
END FindCharSet;
PROCEDURE FindSub(t, sub: T; VAR index: CARDINAL): BOOLEAN RAISES {} =
VAR
i: CARDINAL := index;
lt: CARDINAL := Text.Length(t);
lsub: CARDINAL := Text.Length(sub);
BEGIN
IF i > lt THEN <*FATAL BadFind*> BEGIN RAISE BadFind END; END;
IF lsub = 0 THEN
RETURN TRUE
ELSE
IF lsub <= lt THEN
VAR
lastStart := lt - lsub;
firstCh := Text.GetChar (sub, 0);
BEGIN
WHILE i <= lastStart DO
IF Text.GetChar (t, i) = firstCh THEN
VAR
j: CARDINAL := 1;
BEGIN
LOOP
IF j = lsub THEN
index := i;
RETURN TRUE;
ELSIF i + j >= lt
OR Text.GetChar (t, i+j) # Text.GetChar (sub, j) THEN
EXIT
ELSE
INC(j);
END;
END;
END;
END;
INC(i);
END;
END;
END;
index := lt;
RETURN FALSE;
END;
END FindSub;
<*INLINE*> PROCEDURE Extract(t: T; fx, tx: CARDINAL): T RAISES {} =
BEGIN
RETURN Text.Sub(t, fx, tx-fx);
END Extract;
EXCEPTION
JoinFailed;
PROCEDURE Join(t1, t2, t3, t4, t5: T := NIL): T RAISES {}=
VAR
a := ARRAY [0..4] OF T {t1, t2, t3, t4, t5};
pos := LAST(a);
BEGIN
LOOP
IF a[pos] # NIL THEN
RETURN JoinN(SUBARRAY(a, 0, pos + 1));
ELSIF pos = 0 THEN
<*FATAL JoinFailed*> BEGIN RAISE JoinFailed; END;
ELSE
DEC(pos);
END;
END;
END Join;
PROCEDURE JoinN(READONLY texts: ARRAY OF TEXT): T RAISES {}=
VAR
n := NUMBER(texts);
result: Text8.T;
BEGIN
IF n = 0 THEN <*FATAL JoinFailed*> BEGIN RAISE JoinFailed END; END;
VAR
length := 0;
BEGIN
FOR i := 0 TO n - 1 DO INC(length, Text.Length(texts[i])) END;
result := Text8.Create(length);
END;
VAR
pos := 0;
BEGIN
FOR i := 0 TO n - 1 DO
WITH t = texts[i], tl = Text.Length(t) DO
IF tl > 0 THEN
Text.SetChars (SUBARRAY(result.contents^, pos, tl), t);
INC(pos, tl);
END;
END;
END; (* for *)
END;
RETURN result;
END JoinN;
CONST
Multiplier = -1664117991;
(* = LOOPHOLE( ROUND( .6125423371 * 2^32 ), INTEGER ) *)
PROCEDURE CIHash (t: T): INTEGER =
VAR
result := 0;
len := Text.Length (t);
start := 0;
cnt : INTEGER;
buf : ARRAY [0..255] OF CHAR;
BEGIN
WHILE (start < len) DO
cnt := MIN (len - start, NUMBER (buf));
Text.SetChars (buf, t, start);
FOR i := 0 TO cnt-1 DO
result := result * Multiplier + ORD (ASCII.Upper[buf [i]]);
END;
INC (start, cnt);
END;
RETURN result;
END CIHash;
BEGIN
END TextExtras.