diff options
Diffstat (limited to 'lib/stdlib/src/lists.erl')
| -rw-r--r-- | lib/stdlib/src/lists.erl | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/lib/stdlib/src/lists.erl b/lib/stdlib/src/lists.erl index 62b6ca8a21..af9d63ddd6 100644 --- a/lib/stdlib/src/lists.erl +++ b/lib/stdlib/src/lists.erl @@ -1,7 +1,7 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 1996-2013. All Rights Reserved. +%% Copyright Ericsson AB 1996-2016. All Rights Reserved. %% %% Licensed under the Apache License, Version 2.0 (the "License"); %% you may not use this file except in compliance with the License. @@ -39,7 +39,8 @@ -export([all/2,any/2,map/2,flatmap/2,foldl/3,foldr/3,filter/2, partition/2,zf/2,filtermap/2, mapfoldl/3,mapfoldr/3,foreach/2,takewhile/2,dropwhile/2,splitwith/2, - split/2]). + split/2, + join/2]). %%% BIFs -export([keyfind/3, keymember/3, keysearch/3, member/2, reverse/2]). @@ -1439,6 +1440,18 @@ split(N, [H|T], R) -> split(_, [], _) -> badarg. +-spec join(Sep, List1) -> List2 when + Sep :: T, + List1 :: [T], + List2 :: [T], + T :: term(). + +join(_Sep, []) -> []; +join(Sep, [H|T]) -> [H|join_prepend(Sep, T)]. + +join_prepend(_Sep, []) -> []; +join_prepend(Sep, [H|T]) -> [Sep,H|join_prepend(Sep,T)]. + %%% ================================================================= %%% Here follows the implementation of the sort functions. %%% @@ -2267,6 +2280,8 @@ ukeysplit_2(I, Y, EY, [Z | L], R) -> ukeysplit_2(_I, Y, _EY, [], R) -> [Y | R]. +-dialyzer({no_improper_lists, ukeymergel/3}). + ukeymergel(I, [T1, [H2 | T2], [H3 | T3] | L], Acc) -> %% The fourth argument, [H2 | H3] (=HdM), may confuse type %% checkers. Its purpose is to ensure that the tests H2 == HdM |