Added sticky selection hook.

index.js

@@ -7,7 +7,7 @@ export default {
 	plant: plant,
 
 	use: use,
-	memo: memo,	
+	memo: memo,
 };
 
 export * from './options';
@@ -16,3 +16,4 @@ export * from './hooks';
 export * from './async-rendering-cycle';
 export * from './async-rendering-interrupted';
 export * from './async-save-buffer';
+export * from './sticky-selection';

sticky-selection.js

@@ -0,0 +1,57 @@
+import { useEffect } from 'react';
+
+function useStickySelection(inputRefs) {
+    if (!(inputRefs instanceof Array)) {
+        inputRefs = [ inputRefs ];
+    }
+    var inputs = inputRefs.map(function(inputRef) {
+        var node = inputRef.current;
+        if (node) {
+            return {
+                node: node,
+                value: node.value,
+                start: node.selectionStart,
+                end: node.selectionEnd,
+            };
+        }
+    });
+
+    useEffect(function() {
+        inputs.forEach(function(input) {
+            if (input) {
+                var node = input.node;
+                var previous = input.value;
+                var current = node.value;
+                if (previous !== current) {
+                    var start = findNewPosition(input.start, previous, current);
+                    var end = findNewPosition(input.end, previous, current);
+                    if (typeof(start) === 'number' && typeof(end) === 'number') {
+                        node.selectionStart = start;
+                        node.selectionEnd = end;
+                    }
+                }
+            }
+        });
+    });
+}
+
+function findNewPosition(index, previous, current) {
+    if (typeof(index) === 'number') {
+        if (typeof(previous) === 'string' && typeof(current) === 'string') {
+            var before = previous.substr(0, index);
+            var index1 = current.indexOf(before);
+            if (index1 !== -1) {
+                return index1 + before.length;
+            }
+            var after = previous.substr(index);
+            var index2 = current.lastIndexOf(after);
+            if (index2 !== -1) {
+                return index2;
+            }
+        }
+    }
+}
+
+export {
+    useStickySelection
+};