NetNews Usenet Archive 1992 #27/NN_1992_27.iso/spool/comp/lang/pascal/6799

Internet Message Format | 1992-11-21 | 1.4 KB

Path: sparky!uunet!zaphod.mps.ohio-state.edu!darwin.sura.net!lhc!adm!news
From: [e-mail] (Paul Robinson)
Newsgroups: comp.lang.pascal
Subject: String (2/4)
Message-ID: <[e-mail]>
Date: 21 Nov 92 17:21:27 GMT
Sender: [e-mail]
Lines: 75

The Start and Span parameters in the following procedures

define a substring beginning at position Start (between

characters Start-1 and Start) with a length of Abs(Span).

If Span is positive, the substring is to the right of Start;

if negative, the substring is to the left.



Delete(S,Start,Span) - deletes the substring defined by

  Start, Span from the string S.



Substring(T,S,Start,Span) - the substring of string S

  defined by Start, Span is assigned to the target string T.

}

const   stringmax=100;

type    string=record

           len: 0..stringmax;

           ch: packed array[1..stringmax] of char

           end;



function len(VAR s:string):integer;

begin   len:= s.len

end;



procedure clear(var s:string);

var     i: integer;

begin   s.len:=0;

        for i:=1 to stringmax do s.ch[i]:=' '

end;



procedure concatenate(var s:string; VAR t:string);

var     i,j: integer;

begin

        if s.len+t.len>stringmax

           then j:=stringmax-s.len { overflow }

           else j:=t.len;

        for i:=1 to j do s.ch[s.len+i]:=t.ch[i];

        s.len:=s.len+j;

end;