From mboxrd@z Thu Jan  1 00:00:00 1970
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From: maggiejohn@aol.com (MaggieJohn)
Subject: Re: integer'image
Date: 2000/04/19
Message-ID: <20000419001245.10259.00001322@ng-ci1.aol.com>#1/1
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References: <29IK4.5459$sB3.3596@news.indigo.ie>
Organization: AOL http://www.aol.com
Newsgroups: comp.lang.ada
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Date: 2000-04-19T00:00:00+00:00
List-Id: <comp.lang.ada>

You are getting the exception because there is always a space at the beginning
of an integer'image for a '-' sign.    

Try this one:

procedure make_a_string( thing : string  ) is
    len : natural := thing'len;
     this_string : string(1..len );
begin
      -- do whatever
end;

for x in 1..20 loop
     make_a_string( integer'image(x));
end loop;