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-rw-r--r--lib/stdlib/src/queue.erl123
1 files changed, 93 insertions, 30 deletions
diff --git a/lib/stdlib/src/queue.erl b/lib/stdlib/src/queue.erl
index c09079e8d2..4c6b4d710b 100644
--- a/lib/stdlib/src/queue.erl
+++ b/lib/stdlib/src/queue.erl
@@ -1,7 +1,7 @@
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 1996-2009. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2011. 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
@@ -56,14 +56,16 @@
new() -> {[],[]}. %{RearList,FrontList}
%% O(1)
--spec is_queue(term()) -> boolean().
+-spec is_queue(Term) -> boolean() when
+ Term :: term().
is_queue({R,F}) when is_list(R), is_list(F) ->
true;
is_queue(_) ->
false.
%% O(1)
--spec is_empty(queue()) -> boolean().
+-spec is_empty(Q) -> boolean() when
+ Q :: queue().
is_empty({[],[]}) ->
true;
is_empty({In,Out}) when is_list(In), is_list(Out) ->
@@ -72,14 +74,16 @@ is_empty(Q) ->
erlang:error(badarg, [Q]).
%% O(len(Q))
--spec len(queue()) -> non_neg_integer().
+-spec len(Q) -> non_neg_integer() when
+ Q :: queue().
len({R,F}) when is_list(R), is_list(F) ->
length(R)+length(F);
len(Q) ->
erlang:error(badarg, [Q]).
%% O(len(Q))
--spec to_list(queue()) -> list().
+-spec to_list(Q) -> list() when
+ Q :: queue().
to_list({In,Out}) when is_list(In), is_list(Out) ->
Out++lists:reverse(In, []);
to_list(Q) ->
@@ -88,7 +92,8 @@ to_list(Q) ->
%% Create queue from list
%%
%% O(length(L))
--spec from_list(list()) -> queue().
+-spec from_list(L) -> queue() when
+ L :: list().
from_list(L) when is_list(L) ->
f2r(L);
from_list(L) ->
@@ -97,7 +102,9 @@ from_list(L) ->
%% Return true or false depending on if element is in queue
%%
%% O(length(Q)) worst case
--spec member(term(), queue()) -> boolean().
+-spec member(Item, Q) -> boolean() when
+ Item :: term(),
+ Q :: queue().
member(X, {R,F}) when is_list(R), is_list(F) ->
lists:member(X, R) orelse lists:member(X, F);
member(X, Q) ->
@@ -110,7 +117,10 @@ member(X, Q) ->
%% Put at least one element in each list, if it is cheap
%%
%% O(1)
--spec in(term(), queue()) -> queue().
+-spec in(Item, Q1) -> Q2 when
+ Item :: term(),
+ Q1 :: queue(),
+ Q2 :: queue().
in(X, {[_]=In,[]}) ->
{[X], In};
in(X, {In,Out}) when is_list(In), is_list(Out) ->
@@ -122,7 +132,10 @@ in(X, Q) ->
%% Put at least one element in each list, if it is cheap
%%
%% O(1)
--spec in_r(term(), queue()) -> queue().
+-spec in_r(Item, Q1) -> Q2 when
+ Item :: term(),
+ Q1 :: queue(),
+ Q2 :: queue().
in_r(X, {[],[_]=F}) ->
{F,[X]};
in_r(X, {R,F}) when is_list(R), is_list(F) ->
@@ -133,7 +146,10 @@ in_r(X, Q) ->
%% Take from head/front
%%
%% O(1) amortized, O(len(Q)) worst case
--spec out(queue()) -> {'empty' | {'value',term()}, queue()}.
+-spec out(Q1) -> Result when
+ Q1 :: queue(),
+ Q2 :: queue(),
+ Result :: {{value, Item :: term()}, Q2} | {empty, Q1}.
out({[],[]}=Q) ->
{empty,Q};
out({[V],[]}) ->
@@ -151,7 +167,10 @@ out(Q) ->
%% Take from tail/rear
%%
%% O(1) amortized, O(len(Q)) worst case
--spec out_r(queue()) -> {'empty' | {'value',term()}, queue()}.
+-spec out_r(Q1) -> Result when
+ Q1 :: queue(),
+ Q2 :: queue(),
+ Result :: {{value, Item :: term()}, Q2} | {empty, Q1}.
out_r({[],[]}=Q) ->
{empty,Q};
out_r({[],[V]}) ->
@@ -172,7 +191,9 @@ out_r(Q) ->
%% Return the first element in the queue
%%
%% O(1) since the queue is supposed to be well formed
--spec get(queue()) -> term().
+-spec get(Q) -> Item when
+ Q :: queue(),
+ Item :: term().
get({[],[]}=Q) ->
erlang:error(empty, [Q]);
get({R,F}) when is_list(R), is_list(F) ->
@@ -191,7 +212,9 @@ get([_|R], []) -> % malformed queue -> O(len(Q))
%% Return the last element in the queue
%%
%% O(1) since the queue is supposed to be well formed
--spec get_r(queue()) -> term().
+-spec get_r(Q) -> Item when
+ Q :: queue(),
+ Item :: term().
get_r({[],[]}=Q) ->
erlang:error(empty, [Q]);
get_r({[H|_],F}) when is_list(F) ->
@@ -206,7 +229,9 @@ get_r(Q) ->
%% Return the first element in the queue
%%
%% O(1) since the queue is supposed to be well formed
--spec peek(queue()) -> 'empty' | {'value',term()}.
+-spec peek(Q) -> 'empty' | {'value',Item} when
+ Q :: queue(),
+ Item :: term().
peek({[],[]}) ->
empty;
peek({R,[H|_]}) when is_list(R) ->
@@ -221,7 +246,9 @@ peek(Q) ->
%% Return the last element in the queue
%%
%% O(1) since the queue is supposed to be well formed
--spec peek_r(queue()) -> 'empty' | {'value',term()}.
+-spec peek_r(Q) -> 'empty' | {'value',Item} when
+ Q :: queue(),
+ Item :: term().
peek_r({[],[]}) ->
empty;
peek_r({[H|_],F}) when is_list(F) ->
@@ -236,7 +263,9 @@ peek_r(Q) ->
%% Remove the first element and return resulting queue
%%
%% O(1) amortized
--spec drop(queue()) -> queue().
+-spec drop(Q1) -> Q2 when
+ Q1 :: queue(),
+ Q2 :: queue().
drop({[],[]}=Q) ->
erlang:error(empty, [Q]);
drop({[_],[]}) ->
@@ -254,7 +283,9 @@ drop(Q) ->
%% Remove the last element and return resulting queue
%%
%% O(1) amortized
--spec drop_r(queue()) -> queue().
+-spec drop_r(Q1) -> Q2 when
+ Q1 :: queue(),
+ Q2 :: queue().
drop_r({[],[]}=Q) ->
erlang:error(empty, [Q]);
drop_r({[],[_]}) ->
@@ -275,7 +306,9 @@ drop_r(Q) ->
%% Return reversed queue
%%
%% O(1)
--spec reverse(queue()) -> queue().
+-spec reverse(Q1) -> Q2 when
+ Q1 :: queue(),
+ Q2 :: queue().
reverse({R,F}) when is_list(R), is_list(F) ->
{F,R};
reverse(Q) ->
@@ -285,7 +318,10 @@ reverse(Q) ->
%%
%% Q2 empty: O(1)
%% else: O(len(Q1))
--spec join(queue(), queue()) -> queue().
+-spec join(Q1, Q2) -> Q3 when
+ Q1 :: queue(),
+ Q2 :: queue(),
+ Q3 :: queue().
join({R,F}=Q, {[],[]}) when is_list(R), is_list(F) ->
Q;
join({[],[]}, {R,F}=Q) when is_list(R), is_list(F) ->
@@ -299,7 +335,11 @@ join(Q1, Q2) ->
%%
%% N = 0..len(Q)
%% O(max(N, len(Q)))
--spec split(non_neg_integer(), queue()) -> {queue(),queue()}.
+-spec split(N, Q1) -> {Q2,Q3} when
+ N :: non_neg_integer(),
+ Q1 :: queue(),
+ Q2 :: queue(),
+ Q3 :: queue().
split(0, {R,F}=Q) when is_list(R), is_list(F) ->
{{[],[]},Q};
split(N, {R,F}=Q) when is_integer(N), N >= 1, is_list(R), is_list(F) ->
@@ -340,7 +380,10 @@ split_r1_to_f2(N, [X|R1], F1, R2, F2) ->
%%
%% Fun(_) -> List: O(length(List) * len(Q))
%% else: O(len(Q)
--spec filter(fun((term()) -> boolean() | list()), queue()) -> queue().
+-spec filter(Fun, Q1) -> Q2 when
+ Fun :: fun((Item :: term()) -> boolean() | list()),
+ Q1 :: queue(),
+ Q2 :: queue().
filter(Fun, {R0,F0}) when is_function(Fun, 1), is_list(R0), is_list(F0) ->
F = filter_f(Fun, F0),
R = filter_r(Fun, R0),
@@ -416,7 +459,10 @@ filter_r(Fun, [X|R0]) ->
%% Cons to head
%%
--spec cons(term(), queue()) -> queue().
+-spec cons(Item, Q1) -> Q2 when
+ Item :: term(),
+ Q1 :: queue(),
+ Q2 :: queue().
cons(X, Q) ->
in_r(X, Q).
@@ -425,7 +471,9 @@ cons(X, Q) ->
%% Return the first element in the queue
%%
%% O(1) since the queue is supposed to be well formed
--spec head(queue()) -> term().
+-spec head(Q) -> Item when
+ Q :: queue(),
+ Item :: term().
head({[],[]}=Q) ->
erlang:error(empty, [Q]);
head({R,F}) when is_list(R), is_list(F) ->
@@ -435,7 +483,9 @@ head(Q) ->
%% Remove head element and return resulting queue
%%
--spec tail(queue()) -> queue().
+-spec tail(Q1) -> Q2 when
+ Q1 :: queue(),
+ Q2 :: queue().
tail(Q) ->
drop(Q).
@@ -443,22 +493,35 @@ tail(Q) ->
%% Cons to tail
%%
--spec snoc(queue(), term()) -> queue().
+-spec snoc(Q1, Item) -> Q2 when
+ Q1 :: queue(),
+ Q2 :: queue(),
+ Item :: term().
snoc(Q, X) ->
in(X, Q).
%% Return last element
--spec daeh(queue()) -> term().
+-spec daeh(Q) -> Item when
+ Q :: queue(),
+ Item :: term().
daeh(Q) -> get_r(Q).
--spec last(queue()) -> term().
+-spec last(Q) -> Item when
+ Q :: queue(),
+ Item :: term().
last(Q) -> get_r(Q).
%% Remove last element and return resulting queue
--spec liat(queue()) -> queue().
+-spec liat(Q1) -> Q2 when
+ Q1 :: queue(),
+ Q2 :: queue().
liat(Q) -> drop_r(Q).
--spec lait(queue()) -> queue().
+-spec lait(Q1) -> Q2 when
+ Q1 :: queue(),
+ Q2 :: queue().
lait(Q) -> drop_r(Q). %% Oops, mis-spelled 'tail' reversed. Forget this one.
--spec init(queue()) -> queue().
+-spec init(Q1) -> Q2 when
+ Q1 :: queue(),
+ Q2 :: queue().
init(Q) -> drop_r(Q).
%%--------------------------------------------------------------------------
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-06 09:15:34 +0000