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61 行
1.5 KiB
61 行
1.5 KiB
-module(utMapsFold).
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-export([fold/1, diff/2, diffKeys/2]).
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fold(Map) ->
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fold(maps:iterator(Map), []).
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fold(Iterator, AccList) ->
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case maps:next(Iterator) of
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{Key, Value, NextIter} ->
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fold(NextIter, [{Key, Value} | AccList]);
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none ->
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AccList
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end.
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diff(Map1, Map2) ->
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case map_size(Map1) =< map_size(Map2) of
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true ->
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diff_1(maps:next(maps:iterator(Map1)), Map1, Map2);
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_ ->
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diff_2(maps:next(maps:iterator(Map2)), Map1)
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end.
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diff_1(none, Map1, _Map2) ->
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Map1;
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diff_1({Key, _Value, NextIter}, Map1, Map2) ->
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case maps:is_key(Key, Map2) of
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true ->
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diff_1(maps:next(NextIter), maps:remove(Key, Map1), Map2);
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_ ->
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diff_1(maps:next(NextIter), Map1, Map2)
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end.
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diff_2(none, Map1) ->
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Map1;
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diff_2({Key, _Value, NextIter}, Map1) ->
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diff_2(maps:next(NextIter), maps:remove(Key, Map1)).
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diffKeys(Map1, Map2) ->
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case map_size(Map1) =< map_size(Map2) of
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true ->
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diffKeys_1(maps:next(maps:iterator(Map1)), Map2, []);
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_ ->
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diffKeys_2(maps:next(maps:iterator(Map2)), Map1)
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end.
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diffKeys_1(none, _Map2, Acc) ->
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Acc;
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diffKeys_1({Key, _Value, NextIter}, Map2, Acc) ->
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case maps:is_key(Key, Map2) of
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true ->
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diffKeys_1(maps:next(NextIter), Map2, Acc);
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_ ->
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diffKeys_1(maps:next(NextIter), Map2, [Key | Acc])
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end.
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diffKeys_2(none, Map1) ->
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maps:to_list(Map1);
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diffKeys_2({Key, _Value, NextIter}, Map1) ->
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diffKeys_2(maps:next(NextIter), maps:remove(Key, Map1)).
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