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From: tmoran@acm.org
Newsgroups: comp.lang.ada
Subject: Re: Optimising string handling in application
References: <1049198066.356477@edh3>
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Date: Wed, 02 Apr 2003 04:10:59 GMT
Xref: archiver1.google.com comp.lang.ada:35877
Date: 2003-04-02T04:10:59+00:00
List-Id: <comp.lang.ada>

Does this (with its questions answered) do what you want?

  function Replace_Callsign_In_Msg(Msg          : in String;
                                   New_Callsign : in String) return String is
    Eq : constant Positive := Ada.Strings.Fixed.Index(Msg, "ME001=") + 5;
    Semi : Natural;
  begin
    if Eq = 5 then
      -- "ME001=" not present, what to do?
    end if;
    Semi := Ada.Strings.Fixed(Msg(Eq, ";");
    if Semi = 0 then
      -- following ';' missing, what to do?
    end if;
    return Msg(Msg'first .. Eq) & New_Callsign & Msg(Semi .. Msg'last);
  end Replace_Callsign_In_Msg;