diff options
Diffstat (limited to 'lib/stdlib/src/maps.erl')
-rw-r--r-- | lib/stdlib/src/maps.erl | 91 |
1 files changed, 58 insertions, 33 deletions
diff --git a/lib/stdlib/src/maps.erl b/lib/stdlib/src/maps.erl index 0da12cf8e2..2f2dd41979 100644 --- a/lib/stdlib/src/maps.erl +++ b/lib/stdlib/src/maps.erl @@ -24,7 +24,7 @@ map/2, size/1, update_with/3, update_with/4, without/2, with/2, - iterator/1, next/1]). + iterator/1, iterator/2, next/1]). %% BIFs -export([get/2, find/2, from_list/1, @@ -32,10 +32,13 @@ new/0, put/3, remove/2, take/2, to_list/1, update/3, values/1]). --opaque iterator() :: [{term(), term()}] | [[pos_integer() | map()]]. +-opaque iterator() :: {non_neg_integer() | none | list(term()), map()} + | list({term(), term()}). -export_type([iterator/0]). +-define(IS_ITERATOR(I), (is_list(I) orelse (is_map(element(2,I) andalso (is_list(element(1,I) orelse is_integer(element(1,I)))))))). + %% Shadowed by erl_bif_types: maps:get/2 -spec get(Key,Map) -> Value when Key :: term(), @@ -44,7 +47,6 @@ get(_,_) -> erlang:nif_error(undef). - -spec find(Key,Map) -> {ok, Value} | error when Key :: term(), Map :: map(), @@ -197,15 +199,17 @@ get(Key,Map,Default) -> erlang:error({badmap,Map},[Key,Map,Default]). --spec filter(Pred,Map1) -> Map2 when +-spec filter(Pred,MapOrIter) -> Map when Pred :: fun((Key, Value) -> boolean()), Key :: term(), Value :: term(), - Map1 :: map(), - Map2 :: map(). + MapOrIter :: map() | iterator(), + Map :: map(). filter(Pred,Map) when is_function(Pred,2), is_map(Map) -> - maps:from_list(filter_1(Pred, iterator(Map))); + maps:from_list([{K,V}||{K,V}<-maps:to_list(Map),Pred(K,V)]); +filter(Pred,Iterator) when is_function(Pred,2), ?IS_ITERATOR(Iterator) -> + maps:from_list(filter_1(Pred, Iterator)); filter(Pred,Map) -> erlang:error(error_type(Map),[Pred,Map]). @@ -222,18 +226,20 @@ filter_1(Pred, Iter) -> [] end. --spec fold(Fun,Init,Map) -> Acc when +-spec fold(Fun,Init,MapOrIter) -> Acc when Fun :: fun((K, V, AccIn) -> AccOut), Init :: term(), Acc :: term(), AccIn :: term(), AccOut :: term(), - Map :: map(), + MapOrIter :: map() | iterator(), K :: term(), V :: term(). fold(Fun,Init,Map) when is_function(Fun,3), is_map(Map) -> - fold_1(Fun, Init, iterator(Map)); + lists:foldl(fun({K,V},A) -> Fun(K,V,A) end,Init,maps:to_list(Map)); +fold(Fun,Init,Iterator) when is_function(Fun,3), ?IS_ITERATOR(Iterator) -> + fold_1(Fun,Init,Iterator); fold(Fun,Init,Map) -> erlang:error(error_type(Map),[Fun,Init,Map]). @@ -245,16 +251,18 @@ fold_1(Fun, Acc, Iter) -> Acc end. --spec map(Fun,Map1) -> Map2 when +-spec map(Fun,MapOrIter) -> Map when Fun :: fun((K, V1) -> V2), - Map1 :: map(), - Map2 :: map(), + MapOrIter :: map() | iterator(), + Map :: map(), K :: term(), V1 :: term(), V2 :: term(). map(Fun,Map) when is_function(Fun, 2), is_map(Map) -> - maps:from_list(map_1(Fun, iterator(Map))); + maps:from_list([{K,Fun(K,V)}||{K,V}<-maps:to_list(Map)]); +map(Fun,Iterator) when is_function(Fun, 2), ?IS_ITERATOR(Iterator) -> + maps:from_list(map_1(Fun, Iterator)); map(Fun,Map) -> erlang:error(error_type(Map),[Fun,Map]). @@ -278,28 +286,45 @@ size(Val) -> Map :: map(), Iterator :: iterator(). -iterator(Map) when is_map(Map) -> - case maps:size(Map) < 42 of - true -> maps:to_list(Map); - false -> [[1 | Map]] +iterator(M) when is_map(M) -> iterator(M, #{}); +iterator(M) -> erlang:error({badmap, M}, [M]). + +-spec iterator(Map, Opts) -> Iterator when + Map :: map(), + Opts :: #{ ordered => boolean(), optimize => speed | memory }, + Iterator :: iterator(). +iterator(M, Opts) when is_map(M), is_map(Opts) -> + case maps:merge(default_iterator_opts(), Opts) of + #{ ordered := true, optimize := speed} -> lists:sort(maps:to_list(M)); + #{ ordered := false, optimize := speed} -> maps:to_list(M); + #{ ordered := true, optimize := memory} -> {lists:sort(maps:keys(M)), M}; + #{ ordered := false, optimize := memory} -> {0, M} end; -iterator(M) -> - erlang:error(error_type(M),[M]). +iterator(M, Opts) when is_map(M) -> + erlang:error({badmap, M}, [M, Opts]); +iterator(M, Opts) -> + erlang:error(error_type(M), [M, Opts]). + +default_iterator_opts() -> + #{ ordered => false, optimize => speed }. --spec next(Iterator) -> {K,V,NextIterator} | 'none' when +-spec next(Iterator) -> {Key, Value, NextIterator} | 'none' when Iterator :: iterator(), - K :: term(), - V :: term(), + Key :: term(), + Value :: term(), NextIterator :: iterator(). -next([]) -> none; -next([[Index | Map] | St]) -> - case erts_internal:map_get_index(Index, Map) of - SubMap when is_map(SubMap) -> next([[1 | SubMap], [Index+1|Map] | St]); - [K|V] -> {K,V,[[Index+1 | Map] | St]}; - none -> next(St) - end; -next([{K, V} | I]) -> - {K, V, I}. +next([{K, V} | T]) -> + {K, V, T}; +next([]) -> + none; +next({I, M}) when is_map(M), is_integer(I) orelse is_atom(I) -> + erts_internal:map_next(I, M); +next({[K | T], M}) when is_map(M) -> + {K, maps:get(K, M), {T, M}}; +next({[], M}) when is_map(M) -> + none; +next(Iter) -> + erlang:error(badarg, [Iter]). -spec without(Ks,Map1) -> Map2 when Ks :: [K], @@ -332,5 +357,5 @@ with(Ks,M) -> erlang:error(error_type(M),[Ks,M]). -error_type(M) when is_map(M) -> badarg; +error_type(M) when is_map(M); ?IS_ITERATOR(M) -> badarg; error_type(V) -> {badmap, V}. |