From 0916c5c6e536affca1f6f0c7693d68fb64843c1c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Micha=C5=82=20Muska=C5=82a?= Date: Tue, 17 Jul 2018 18:38:10 +0200 Subject: maps:new/0 is no longer a BIF Implementing it in Erlang allows taking advantage of the literal pool optimisation, this means the function implemented in Erlang does no allocations, while the BIF had to allocate new map each time it was called. Benchmarks show the function is also slightly faster now. --- lib/stdlib/src/maps.erl | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) (limited to 'lib/stdlib') diff --git a/lib/stdlib/src/maps.erl b/lib/stdlib/src/maps.erl index 60463feec2..6f5553c769 100644 --- a/lib/stdlib/src/maps.erl +++ b/lib/stdlib/src/maps.erl @@ -21,7 +21,7 @@ -module(maps). -export([get/3, filter/2,fold/3, - map/2, size/1, + map/2, size/1, new/0, update_with/3, update_with/4, without/2, with/2, iterator/1, next/1]). @@ -29,7 +29,7 @@ %% BIFs -export([get/2, find/2, from_list/1, is_key/2, keys/1, merge/2, - new/0, put/3, remove/2, take/2, + put/3, remove/2, take/2, to_list/1, update/3, values/1]). -opaque iterator() :: {term(), term(), iterator()} @@ -91,13 +91,6 @@ keys(_) -> erlang:nif_error(undef). merge(_,_) -> erlang:nif_error(undef). - --spec new() -> Map when - Map :: map(). - -new() -> erlang:nif_error(undef). - - %% Shadowed by erl_bif_types: maps:put/3 -spec put(Key,Value,Map1) -> Map2 when Key :: term(), @@ -157,6 +150,11 @@ values(_) -> erlang:nif_error(undef). %% End of BIFs +-spec new() -> Map when + Map :: #{}. + +new() -> #{}. + -spec update_with(Key,Fun,Map1) -> Map2 when Key :: term(), Map1 :: map(), -- cgit v1.2.3