Data commit

Task/Copy-stdin-to-stdout/Mercury/copy-stdin-to-stdout.mercury

@@ -0,0 +1,41 @@
+:- module stdin_to_stdout.
+:- interface.
+
+:- import_module io.
+
+:- pred main(io::di, io::uo) is det.
+
+%-----------------------------------------------------------------------------%
+%-----------------------------------------------------------------------------%
+
+:- implementation.
+
+:- import_module char.
+:- import_module list.
+:- import_module string.
+
+%-----------------------------------------------------------------------------%
+
+
+
+main(!IO) :-
+    io.read_line_as_string(Result, !IO),
+    (
+        Result = ok(Line),
+        io.write_string(Line, !IO),
+        main(!IO)
+    ;
+        Result = eof
+    ;
+        Result = error(Error),
+        io.error_message(Error, Message),
+        io.input_stream_name(StreamName, !IO),
+        io.progname("stdin_to_stdout", ProgName, !IO),
+        io.write_strings([
+            ProgName, ": ",
+            "error reading from `", StreamName, "': \n\t",
+            Message, "\n"
+        ], !IO)
+    ).
+
+%-----------------------------------------------------------------------------%