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69dbd420d9
Add predicates for reading and writing int8s and uint8s with binary file
streams.
Document the predicates that are used to write fixed size integer types
to text file streams properly.
library/io.m:
As above.
tests/hard_coded/Mmakefile:
tests/hard_coded/write_binary_uint8.{m,exp}:
tests/hard_coded/write_binary_int8.{m,exp}:
Test the new predicates.
100 lines
2.7 KiB
Mathematica
100 lines
2.7 KiB
Mathematica
%---------------------------------------------------------------------------%
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% vim: ft=mercury ts=4 sw=4 et
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%---------------------------------------------------------------------------%
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%
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% Test writing and reading uint8s with binary streams.
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%
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%---------------------------------------------------------------------------%
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:- module write_binary_uint8.
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:- interface.
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:- import_module io.
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:- pred main(io::di, io::uo) is det.
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:- implementation.
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:- import_module int.
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:- import_module list.
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:- import_module uint8.
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main(!IO) :-
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io.make_temp_file(MakeTempResult, !IO),
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(
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MakeTempResult = ok(TempFileName),
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main_2(TempFileName, !IO)
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;
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MakeTempResult = error(Msg),
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io.print_line(Msg, !IO),
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io.set_exit_status(1, !IO)
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).
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:- pred main_2(string::in, io::di, io::uo) is det.
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main_2(FileName, !IO) :-
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io.open_binary_output(FileName, OpenOutputResult, !IO),
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(
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OpenOutputResult = ok(OutputFile),
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list.foldl(write_binary_uint8(OutputFile), data, !IO),
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io.close_binary_output(OutputFile, !IO),
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io.open_binary_input(FileName, OpenInputResult, !IO),
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(
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OpenInputResult = ok(InputFile),
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read_uint8s(InputFile, [], ReadResult, !IO),
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(
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ReadResult = ok(RevUInt8s),
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io.close_binary_input(InputFile, !IO),
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list.reverse(RevUInt8s, UInt8s),
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( if UInt8s = data then
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io.print_line("PASSED", !IO)
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else
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io.print_line("FAILED", !IO)
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)
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;
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ReadResult = error(IO_Error),
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io.error_message(IO_Error, Msg),
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io.print_line(Msg, !IO)
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)
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;
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OpenInputResult = error(IO_Error),
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io.error_message(IO_Error, Msg),
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io.print_line(Msg, !IO)
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)
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;
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OpenOutputResult = error(IO_Error),
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io.error_message(IO_Error, Msg),
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io.print_line(Msg, !IO)
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),
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io.remove_file(FileName, _, !IO).
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:- pred read_uint8s(io.binary_input_stream::in,
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list(uint8)::in, io.res(list(uint8))::out, io::di, io::uo) is det.
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read_uint8s(InputFile, !.Us, Result, !IO) :-
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io.read_binary_uint8(InputFile, ReadResult, !IO),
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(
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ReadResult = ok(U),
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!:Us = [U | !.Us],
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read_uint8s(InputFile, !.Us, Result, !IO)
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;
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ReadResult = eof,
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Result = ok(!.Us)
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;
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ReadResult = error(IO_Error),
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Result = error(IO_Error)
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).
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:- func data = list(uint8).
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data = Uint8s :-
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int.fold_down(add_uint8, 0, 255, [], Uint8s).
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:- pred add_uint8(int::in,
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list(uint8)::in, list(uint8)::out) is det.
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add_uint8(I, !Us) :-
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U = uint8.cast_from_int(I),
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!:Us = [U | !.Us].
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