X-Git-Url: https://git.xandkar.net/?a=blobdiff_plain;f=src%2Fhope_kv_list.erl;h=44a78d40745217dd946779c7f34c99df3faa799c;hb=0ed4baebe135edc50d24d3613c6ee971f75d8c98;hp=7b25797ed3b9ef0b57c660e1f4665a1a45adaba8;hpb=99fd18ae3aa61238700208a5f2b2959c1b1a2d80;p=hope.git

diff --git a/src/hope_kv_list.erl b/src/hope_kv_list.erl
index 7b25797..44a78d4 100644
--- a/src/hope_kv_list.erl
+++ b/src/hope_kv_list.erl
@@ -13,8 +13,9 @@
 
 -export(
     [ empty/0
-    , get/2
-    , get/3
+    , get/2  % get option
+    , get/3  % get existing or default
+    , get/4  % get existing if valid, or default
     , set/3
     , update/3
     , pop/2
@@ -24,6 +25,7 @@
     , fold/3
     , of_kv_list/1
     , to_kv_list/1
+    , has_key/2
     , find_unique_presence_violations/2  % No optional keys
     , find_unique_presence_violations/3  % Specify optional keys
     , validate_unique_presence/2  % No optional keys
@@ -75,6 +77,13 @@ get(T, K, Default) ->
     Vopt = get(T, K),
     hope_option:get(Vopt, Default).
 
+-spec get(t(K, V), K, V, fun((V) -> boolean())) ->
+    V.
+get(T, K, Default, IsValid) ->
+    VOpt1 = get(T, K),
+    VOpt2 = hope_option:validate(VOpt1, IsValid),
+    hope_option:get(VOpt2, Default).
+
 -spec set(t(K, V), K, V) ->
     t(K, V).
 set(T, K, V) ->
@@ -96,7 +105,7 @@ pop(T1, K) ->
     ;   false               -> {none     , T1}
     end.
 
--spec iter(t(K, V), fun((K, V) -> ok)) ->
+-spec iter(t(K, V), fun((K, V) -> any())) ->
     ok.
 iter(T, F1) ->
     F2 = lift_map(F1),
@@ -198,6 +207,10 @@ presence_violations_to_list(#hope_kv_list_presence_violations
         end,
     ErrorDups ++ ErrorMissing ++ ErrorUnsupported.
 
+-spec has_key(t(K, _), K) ->
+    boolean().
+has_key(T, K1) ->
+    lists:any(fun ({K2, _}) -> K1 =:= K2 end, T).
 
 %% ============================================================================
 %% Helpers