From 49df300ffe6f020a4df26dede27bef42d000c671 Mon Sep 17 00:00:00 2001 From: Louis Pilfold Date: Sat, 4 May 2019 22:07:48 +0000 Subject: map_dict:update --- gen/src/map_dict.erl | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) (limited to 'gen/src') diff --git a/gen/src/map_dict.erl b/gen/src/map_dict.erl index 0eea5c2..10150b3 100644 --- a/gen/src/map_dict.erl +++ b/gen/src/map_dict.erl @@ -1,7 +1,7 @@ -module(map_dict). -compile(no_auto_import). --export([size/1, to_list/1, from_list/1, has_key/2, new/0, fetch/2, put/3, map_values/2, keys/1, values/1, filter/2, take/2, drop/2, merge/2, delete/2]). +-export([size/1, to_list/1, from_list/1, has_key/2, new/0, fetch/2, put/3, map_values/2, keys/1, values/1, filter/2, take/2, merge/2, delete/2, drop/2, update/3]). size(A) -> maps:size(A). @@ -54,12 +54,6 @@ erl_take(A, B) -> take(Map, Keys) -> erl_take(Keys, Map). -erl_drop(A, B) -> - maps:without(A, B). - -drop(Map, Keys) -> - erl_drop(Keys, Map). - merge(A, B) -> maps:merge(A, B). @@ -68,3 +62,15 @@ erl_delete(A, B) -> delete(Map, Key) -> erl_delete(Key, Map). + +drop(Map, Keys) -> + list:fold(Keys, Map, fun(Key, Acc) -> delete(Acc, Key) end). + +update(Dict, Key, F) -> + case fetch(Dict, Key) of + {ok, Value} -> + put(Dict, Key, F({ok, Value})); + + {error, _} -> + put(Dict, Key, F({error, not_found})) + end. -- cgit v1.2.3