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Date: Thu, 1 Nov 2018 11:14:34 -0700 (PDT)
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Subject: Re: windows-1251 to utf-8
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Xref: reader02.eternal-september.org comp.lang.ada:54747
Date: 2018-11-01T11:14:34-07:00
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You can use Matreshka's text codecs, here is example.

with Ada.Text_IO;        use Ada.Text_IO;

with AWS.Client;         use AWS.Client;
with AWS.Response;       use AWS.Response;

with League.Strings;     use League.Strings;
with League.Text_Codecs; use League.Text_Codecs;

procedure Main is
   Request_Header_List : Header_List;
   CP1251_Codec        : Text_Codec := Codec (To_Universal_String ("cp1251"));
   Text                : Universal_String;

begin

   Request_Header_List.Add(Name => "User-Agent", Value => "Mozilla/5.0 (X11; Linux x86_64; rv:56.0) Gecko/20100101 Firefox/56.0");

   Text := CP1251_Codec.Decode (Message_Body(Get(URL => "http://www.sql.ru/", Headers => Request_Header_List)));

   Put_Line(Text.To_UTF_8_String);

end Main;