Data commit

Task/Optional-parameters/Erlang/optional-parameters.erl

@@ -0,0 +1,39 @@
+-module( optional_parameters ).
+
+-export( [sort/2, task/0] ).
+
+sort( Table, Options ) ->
+	Ordering = proplists:get_value( ordering, Options, lexicographic ),
+	Column = proplists:get_value( column, Options, 1 ),
+	Is_reverse = proplists:get_value( reverse, Options, false ),
+	Sorted = sort( Table, Ordering, Column ),
+	sorted_reverse( Is_reverse, Sorted ).
+
+task() ->
+	io:fwrite( "sort defaults ~p~n", [sort( table(), [])] ),
+	io:fwrite( "reverse ~p~n", [sort( table(), [reverse])] ),
+	io:fwrite( "sort column 3 ~p~n", [sort( table(), [{column, 3}])] ),
+	io:fwrite( "reverse ~p~n", [sort( table(), [{column, 3}, reverse])] ),
+	io:fwrite( "sort numeric ~p~n", [sort( table(), [{ordering, numeric}])] ),
+	io:fwrite( "reverse ~p~n", [sort( table(), [{ordering, numeric}, reverse])] ).
+
+
+
+row_numeric( Tuple ) -> erlang:list_to_tuple( [{erlang:list_to_integer(X), X} || X <- erlang:tuple_to_list(Tuple)] ).
+
+row_remove_numeric( Tuple ) -> erlang:list_to_tuple( [Y || {_X, Y} <- erlang:tuple_to_list(Tuple)] ).
+
+sort( Table, lexicographic, Column ) -> lists:keysort( Column, Table );
+sort( Table, numeric, Column ) ->
+	Numeric_table = [row_numeric(X) || X <- Table],
+	Sorted_numeric = lists:keysort( Column, Numeric_table ),
+	[row_remove_numeric(X) || X <- Sorted_numeric].
+
+sorted_reverse( true, Sorted ) -> lists:reverse( Sorted );
+sorted_reverse( false, Sorted ) -> Sorted.
+
+table() -> [table_row1(), table_row2(), table_row3()].
+
+table_row1() -> {"123", "456", "0789"}.
+table_row2() -> {"456", "0789", "123"}.
+table_row3() -> {"0789", "123", "456"}.