aboutsummaryrefslogtreecommitdiff
path: root/common/observable.js
diff options
context:
space:
mode:
authorWojtek Kosior <koszko@koszko.org>2021-09-02 18:35:49 +0200
committerWojtek Kosior <koszko@koszko.org>2021-09-02 18:35:49 +0200
commit6247f163d3ca89d5570450ac7ac8fd18f73bb74b (patch)
treee3d4817ae475e1f3553d3a50a77792fc5c3c25a0 /common/observable.js
parent4b59dced912fb9b50ff041c67f0f72cbbad56b6c (diff)
downloadbrowser-extension-6247f163d3ca89d5570450ac7ac8fd18f73bb74b.tar.gz
browser-extension-6247f163d3ca89d5570450ac7ac8fd18f73bb74b.zip
enable toggling of global script blocking policy\n\nThis commit also introduces `light_storage' module which is later going to replace the storage code we use right now.\nAlso included is a hack to properly display scrollbars under Mozilla (needs testing on newer Mozilla browsers).
Diffstat (limited to 'common/observable.js')
-rw-r--r--common/observable.js28
1 files changed, 11 insertions, 17 deletions
diff --git a/common/observable.js b/common/observable.js
index 1fb0b0a..02f1c1b 100644
--- a/common/observable.js
+++ b/common/observable.js
@@ -6,28 +6,22 @@
* Redistribution terms are gathered in the `copyright' file.
*/
-function make()
-{
- return new Set();
-}
+const make = (value=undefined) => ({value, listeners: new Set()});
+const subscribe = (observable, cb) => observable.listeners.add(cb);
+const unsubscribe = (observable, cb) => observable.listeners.delete(cb);
-function subscribe(observable, cb)
-{
- observable.add(cb);
-}
-
-function unsubscribe(observable, cb)
-{
- observable.delete(cb);
-}
+const silent_set = (observable, value) => observable.value = value;
+const broadcast = (observable, ...values) =>
+ observable.listeners.forEach(cb => cb(...values));
-function broadcast(observable, event)
+function set(observable, value)
{
- for (const callback of observable)
- callback(event);
+ const old_value = observable.value;
+ silent_set(observable, value);
+ broadcast(observable, value, old_value);
}
-const observables = {make, subscribe, unsubscribe, broadcast};
+const observables = {make, subscribe, unsubscribe, broadcast, silent_set, set};
/*
* EXPORTS_START