Add constants for controlling how to visit

index.js

@@ -3,6 +3,9 @@
 /* Expose. */
 module.exports = visit;
 
+visit.CONTINUE = true;
+visit.EXIT = false;
+
 var is = require('unist-util-is');
 
 /* Visit. */
@@ -25,7 +28,7 @@ function visit(tree, test, visitor, reverse) {
       result = visitor(node, index, parent || null);
     }
 
-    if (node.children && result !== false) {
+    if (node.children && result !== visit.EXIT) {
       return all(node.children, node);
     }
 
@@ -39,17 +42,19 @@ function visit(tree, test, visitor, reverse) {
     var min = -1;
     var index = (reverse ? max : min) + step;
     var child;
+    var result;
 
     while (index > min && index < max) {
       child = children[index];
+      result = child && one(child, index, parent);
 
-      if (child && one(child, index, parent) === false) {
-        return false;
+      if (result === visit.EXIT) {
+        return result;
       }
 
       index += step;
     }
 
-    return true;
+    return visit.CONTINUE;
   }
 }

readme.md

@@ -62,7 +62,7 @@ since child traversal is determined when the parent is visited.
     This **does not** mean checking starts at the deepest node and
     continues on to the highest node
 
-#### `stop? = visitor(node, index, parent)`
+#### `next? = visitor(node, index, parent)`
 
 Invoked when a node (matching `test`, if given) is found.
 
@@ -74,7 +74,10 @@ Invoked when a node (matching `test`, if given) is found.
 
 ###### Returns
 
-`boolean?` - When `false`, visiting is immediately stopped.
+*   `visit.EXIT` (`false`)
+    — Stop visiting immediately
+*   `visit.CONTINUE` (`true`)
+    — Continue visiting as normal (same behaviour as not returning anything)
 
 ## Related
 
@@ -129,7 +132,7 @@ repository, organisation, or community you agree to abide by its terms.
 
 [is]: https://github.com/syntax-tree/unist-util-is#istest-node-index-parent-context
 
-[visitor]: #stop--visitornode-index-parent
+[visitor]: #next--visitornode-index-parent
 
 [gh-9]: https://github.com/syntax-tree/unist-util-visit/issues/9