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-rw-r--r--lib/stdlib/src/dict.erl131
1 files changed, 62 insertions, 69 deletions
diff --git a/lib/stdlib/src/dict.erl b/lib/stdlib/src/dict.erl
index 4b42f64609..cf8fb3114a 100644
--- a/lib/stdlib/src/dict.erl
+++ b/lib/stdlib/src/dict.erl
@@ -1,8 +1,7 @@
-%% -*- coding: utf-8 -*-
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 2000-2012. All Rights Reserved.
+%% Copyright Ericsson AB 2000-2014. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
@@ -37,11 +36,13 @@
-module(dict).
%% Standard interface.
--export([new/0,is_key/2,to_list/1,from_list/1,size/1]).
+-export([new/0,is_key/2,to_list/1,from_list/1,size/1,is_empty/1]).
-export([fetch/2,find/2,fetch_keys/1,erase/2]).
-export([store/3,append/3,append_list/3,update/3,update/4,update_counter/3]).
-export([fold/3,map/2,filter/2,merge/3]).
+-export_type([dict/0, dict/2]).
+
%% Low-level interface.
%%-export([get_slot/2,get_bucket/2,on_bucket/3,fold_dict/3,
%% maybe_expand/2,maybe_contract/2]).
@@ -54,6 +55,8 @@
-define(exp_size, (?seg_size * ?expand_load)).
-define(con_size, (?seg_size * ?contract_load)).
+-type segs(_Key, _Value) :: tuple().
+
%% Define a hashtable. The default values are the standard ones.
-record(dict,
{size=0 :: non_neg_integer(), % Number of elements
@@ -63,14 +66,13 @@
exp_size=?exp_size :: non_neg_integer(), % Size to expand at
con_size=?con_size :: non_neg_integer(), % Size to contract at
empty :: tuple(), % Empty segment
- segs :: tuple() % Segments
+ segs :: segs(_, _) % Segments
}).
-%% A declaration equivalent to the following one is hard-coded in erl_types.
-%% That declaration contains hard-coded information about the #dict{}
-%% structure and the types of its fields. So, please make sure that any
-%% changes to its structure are also propagated to erl_types.erl.
-%%
-%% -opaque dict() :: #dict{}.
+
+
+-opaque dict() :: dict(_, _).
+
+-opaque dict(Key, Value) :: #dict{segs :: segs(Key, Value)}.
-define(kv(K,V), [K|V]). % Key-Value pair format
%%-define(kv(K,V), {K,V}). % Key-Value pair format
@@ -82,8 +84,7 @@ new() ->
#dict{empty=Empty,segs={Empty}}.
-spec is_key(Key, Dict) -> boolean() when
- Key :: term(),
- Dict :: dict().
+ Dict :: dict(Key, Value :: term()).
is_key(Key, D) ->
Slot = get_slot(D, Key),
@@ -95,15 +96,15 @@ find_key(K, [_|Bkt]) -> find_key(K, Bkt);
find_key(_, []) -> false.
-spec to_list(Dict) -> List when
- Dict :: dict(),
- List :: [{Key :: term(), Value :: term()}].
+ Dict :: dict(Key, Value),
+ List :: [{Key, Value}].
to_list(D) ->
fold(fun (Key, Val, List) -> [{Key,Val}|List] end, [], D).
-spec from_list(List) -> Dict when
- List :: [{Key :: term(), Value :: term()}],
- Dict :: dict().
+ Dict :: dict(Key, Value),
+ List :: [{Key, Value}].
from_list(L) ->
lists:foldl(fun ({K,V}, D) -> store(K, V, D) end, new(), L).
@@ -113,10 +114,13 @@ from_list(L) ->
size(#dict{size=N}) when is_integer(N), N >= 0 -> N.
+-spec is_empty(Dict) -> boolean() when
+ Dict :: dict().
+
+is_empty(#dict{size=N}) -> N =:= 0.
+
-spec fetch(Key, Dict) -> Value when
- Key :: term(),
- Dict :: dict(),
- Value :: term().
+ Dict :: dict(Key, Value).
fetch(Key, D) ->
Slot = get_slot(D, Key),
@@ -131,9 +135,7 @@ fetch_val(K, [_|Bkt]) -> fetch_val(K, Bkt);
fetch_val(_, []) -> throw(badarg).
-spec find(Key, Dict) -> {'ok', Value} | 'error' when
- Key :: term(),
- Dict :: dict(),
- Value :: term().
+ Dict :: dict(Key, Value).
find(Key, D) ->
Slot = get_slot(D, Key),
@@ -145,16 +147,16 @@ find_val(K, [_|Bkt]) -> find_val(K, Bkt);
find_val(_, []) -> error.
-spec fetch_keys(Dict) -> Keys when
- Dict :: dict(),
- Keys :: [term()].
+ Dict :: dict(Key, Value :: term()),
+ Keys :: [Key].
fetch_keys(D) ->
fold(fun (Key, _Val, Keys) -> [Key|Keys] end, [], D).
-spec erase(Key, Dict1) -> Dict2 when
- Key :: term(),
- Dict1 :: dict(),
- Dict2 :: dict().
+ Dict1 :: dict(Key, Value),
+ Dict2 :: dict(Key, Value).
+
%% Erase all elements with key Key.
erase(Key, D0) ->
@@ -170,10 +172,8 @@ erase_key(Key, [E|Bkt0]) ->
erase_key(_, []) -> {[],0}.
-spec store(Key, Value, Dict1) -> Dict2 when
- Key :: term(),
- Value :: term(),
- Dict1 :: dict(),
- Dict2 :: dict().
+ Dict1 :: dict(Key, Value),
+ Dict2 :: dict(Key, Value).
store(Key, Val, D0) ->
Slot = get_slot(D0, Key),
@@ -190,10 +190,8 @@ store_bkt_val(Key, New, [Other|Bkt0]) ->
store_bkt_val(Key, New, []) -> {[?kv(Key,New)],1}.
-spec append(Key, Value, Dict1) -> Dict2 when
- Key :: term(),
- Value :: term(),
- Dict1 :: dict(),
- Dict2 :: dict().
+ Dict1 :: dict(Key, Value),
+ Dict2 :: dict(Key, Value).
append(Key, Val, D0) ->
Slot = get_slot(D0, Key),
@@ -210,10 +208,9 @@ append_bkt(Key, Val, [Other|Bkt0]) ->
append_bkt(Key, Val, []) -> {[?kv(Key,[Val])],1}.
-spec append_list(Key, ValList, Dict1) -> Dict2 when
- Key :: term(),
- ValList :: [Value :: term()],
- Dict1 :: dict(),
- Dict2 :: dict().
+ Dict1 :: dict(Key, Value),
+ Dict2 :: dict(Key, Value),
+ ValList :: [Value].
append_list(Key, L, D0) ->
Slot = get_slot(D0, Key),
@@ -284,10 +281,9 @@ app_list_bkt(Key, L, []) -> {[?kv(Key,L)],1}.
%% {[Other|Bkt1],Dc}.
-spec update(Key, Fun, Dict1) -> Dict2 when
- Key :: term(),
- Fun :: fun((Value1 :: term()) -> Value2 :: term()),
- Dict1 :: dict(),
- Dict2 :: dict().
+ Dict1 :: dict(Key, Value),
+ Dict2 :: dict(Key, Value),
+ Fun :: fun((Value1 :: Value) -> Value2 :: Value).
update(Key, F, D0) ->
Slot = get_slot(D0, Key),
@@ -307,11 +303,10 @@ update_bkt(_Key, _F, []) ->
throw(badarg).
-spec update(Key, Fun, Initial, Dict1) -> Dict2 when
- Key :: term(),
- Initial :: term(),
- Fun :: fun((Value1 :: term()) -> Value2 :: term()),
- Dict1 :: dict(),
- Dict2 :: dict().
+ Dict1 :: dict(Key, Value),
+ Dict2 :: dict(Key, Value),
+ Fun :: fun((Value1 :: Value) -> Value2 :: Value),
+ Initial :: Value.
update(Key, F, Init, D0) ->
Slot = get_slot(D0, Key),
@@ -327,10 +322,9 @@ update_bkt(Key, F, I, [Other|Bkt0]) ->
update_bkt(Key, F, I, []) when is_function(F, 1) -> {[?kv(Key,I)],1}.
-spec update_counter(Key, Increment, Dict1) -> Dict2 when
- Key :: term(),
- Increment :: number(),
- Dict1 :: dict(),
- Dict2 :: dict().
+ Dict1 :: dict(Key, Value),
+ Dict2 :: dict(Key, Value),
+ Increment :: number().
update_counter(Key, Incr, D0) when is_number(Incr) ->
Slot = get_slot(D0, Key),
@@ -347,36 +341,35 @@ counter_bkt(Key, I, []) -> {[?kv(Key,I)],1}.
-spec fold(Fun, Acc0, Dict) -> Acc1 when
Fun :: fun((Key, Value, AccIn) -> AccOut),
- Key :: term(),
- Value :: term(),
- Acc0 :: term(),
- Acc1 :: term(),
- AccIn :: term(),
- AccOut :: term(),
- Dict :: dict().
+ Dict :: dict(Key, Value),
+ Acc0 :: Acc,
+ Acc1 :: Acc,
+ AccIn :: Acc,
+ AccOut :: Acc.
+
%% Fold function Fun over all "bags" in Table and return Accumulator.
fold(F, Acc, D) -> fold_dict(F, Acc, D).
-spec map(Fun, Dict1) -> Dict2 when
- Fun :: fun((Key :: term(), Value1 :: term()) -> Value2 :: term()),
- Dict1 :: dict(),
- Dict2 :: dict().
+ Fun :: fun((Key, Value1) -> Value2),
+ Dict1 :: dict(Key, Value1),
+ Dict2 :: dict(Key, Value2).
map(F, D) -> map_dict(F, D).
-spec filter(Pred, Dict1) -> Dict2 when
- Pred :: fun((Key :: term(), Value :: term()) -> boolean()),
- Dict1 :: dict(),
- Dict2 :: dict().
+ Pred :: fun((Key , Value) -> boolean()),
+ Dict1 :: dict(Key, Value),
+ Dict2 :: dict(Key, Value).
filter(F, D) -> filter_dict(F, D).
-spec merge(Fun, Dict1, Dict2) -> Dict3 when
- Fun :: fun((Key :: term(), Value1 :: term(), Value2 :: term()) -> Value :: term()),
- Dict1 :: dict(),
- Dict2 :: dict(),
- Dict3 :: dict().
+ Fun :: fun((Key, Value1, Value2) -> Value),
+ Dict1 :: dict(Key, Value1),
+ Dict2 :: dict(Key, Value2),
+ Dict3 :: dict(Key, Value).
merge(F, D1, D2) when D1#dict.size < D2#dict.size ->
fold_dict(fun (K, V1, D) ->