www

commit dc465060b27d05d0c9dcca26af261dfeb13f6637
parent 95e6ca37f507d6f9bd340861f3626028d5b5acb3
Author: Suzanne Soy <ligo@suzanne.soy>
Date:   Thu,  1 Apr 2021 00:00:01 +0100

undo,redo

Diffstat:
M
index.html
 | 
18
++++++++++++++++--

1 file changed, 16 insertions(+), 2 deletions(-)
diff --git a/index.html b/index.html
@@ -547,10 +547,22 @@ var module = function(customization) {
     }
 
     function set_current_mod(state, mod) {
-        state.current = state.stack.length;
+        state.stack.splice(state.current + 1, state.stack.length - state.current - 1);
+        state.current++;
         return state.stack[state.current] = mod;
     }
 
+    function undo(state) {
+        state.current--;
+    }
+
+    function redo(state) {
+        state.current++;
+        if (state.current >= state.stack.length) {
+            state.current = state.stack.length - 1;
+        }
+    }
+
     function create_state_from_mod(initial_mod) {
         return { current: 0, stack: [initial_mod] };
     }
@@ -618,7 +630,9 @@ var module = function(customization) {
         create_state,
         serialize,
         deserialize,
-        update_state
+        update_state,
+        undo,
+        redo
     }
 }