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(* This module is obsolete. Don't use it. *)
MODULE Strings2;
IMPORT
Strings;
PROCEDURE AppendChar* (ch: CHAR; VAR dst: ARRAY OF CHAR);
(* Appends 'ch' to string 'dst' (if Length(dst)<LEN(dst)-1). *)
VAR
len: INTEGER;
BEGIN
len := Strings.Length (dst);
IF (len < SHORT (LEN (dst))-1) THEN
dst[len] := ch;
dst[len+1] := 0X
END
END AppendChar;
PROCEDURE InsertChar* (ch: CHAR; pos: INTEGER; VAR dst: ARRAY OF CHAR);
(* Inserts the character ch into the string dst at position pos (0<=pos<=
Length(dst)). If pos=Length(dst), src is appended to dst. If the size of
dst is not large enough to hold the result of the operation, the result is
truncated so that dst is always terminated with a 0X. *)
VAR
src: ARRAY 2 OF CHAR;
BEGIN
src[0] := ch; src[1] := 0X;
Strings.Insert (src, pos, dst)
END InsertChar;
PROCEDURE PosChar* (ch: CHAR; str: ARRAY OF CHAR): INTEGER;
(* Returns the first position of character 'ch' in 'str' or
-1 if 'str' doesn't contain the character.
Ex.: PosChar ("abcd", "c") = 2
PosChar ("abcd", "D") = -1 *)
VAR
i: INTEGER;
BEGIN
i := 0;
LOOP
IF (str[i] = ch) THEN
RETURN i
ELSIF (str[i] = 0X) THEN
RETURN -1
ELSE
INC (i)
END
END
END PosChar;
PROCEDURE Match* (pat, s: ARRAY OF CHAR): BOOLEAN;
(* Returns TRUE if the string in s matches the string in pat.
The pattern may contain any number of the wild characters '*' and '?'
'?' matches any single character
'*' matches any sequence of characters (including a zero length sequence)
E.g. '*.?' will match any string with two or more characters if it's second
last character is '.'. *)
VAR
lenSource,
lenPattern: INTEGER;
PROCEDURE RecMatch(VAR src: ARRAY OF CHAR; posSrc: INTEGER;
VAR pat: ARRAY OF CHAR; posPat: INTEGER): BOOLEAN;
(* src = to be tested , posSrc = position in src *)
(* pat = pattern to match, posPat = position in pat *)
VAR
i: INTEGER;
BEGIN
LOOP
IF (posSrc = lenSource) & (posPat = lenPattern) THEN
RETURN TRUE
ELSIF (posPat = lenPattern) THEN
RETURN FALSE
ELSIF (pat[posPat] = "*") THEN
IF (posPat = lenPattern-1) THEN
RETURN TRUE
ELSE
FOR i := posSrc TO lenSource DO
IF RecMatch (src, i, pat, posPat+1) THEN
RETURN TRUE
END
END;
RETURN FALSE
END
ELSIF (pat[posPat] # "?") & (pat[posPat] # src[posSrc]) THEN
RETURN FALSE
ELSE
INC(posSrc); INC(posPat)
END
END
END RecMatch;
BEGIN
lenPattern := Strings.Length (pat);
lenSource := Strings.Length (s);
RETURN RecMatch (s, 0, pat, 0)
END Match;
END Strings2.
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