flow like the river

BACK_BACK/node_modules/falafel/example/prompt.js

@@ -0,0 +1,49 @@
+var falafel = require('../');
+var vm = require('vm');
+
+var termExps = [
+    'Identifier',
+    'CallExpression',
+    'BinaryExpression',
+    'UpdateExpression',
+    'UnaryExpression'
+].reduce(function (acc, key) { acc[key] = true; return acc }, {});
+
+function terminated (node) {
+    for (var p = node; p.parent; p = p.parent) {
+        if (termExps[p.type]) return true;
+    }
+    return false;
+}
+
+var src = '{"a":[2,~9,prompt(":d")],"b":4,"c":prompt("beep"),"d":6}';
+
+var offsets = [];
+var output = falafel('(' + src + ')', function (node) {
+    var isLeaf = node.parent
+        && !terminated(node.parent) && terminated(node)
+    ;
+    
+    if (isLeaf) {
+        var s = node.source();
+        var prompted = false;
+        var res = vm.runInNewContext('(' + s + ')', {
+            prompt : function (x) {
+                setTimeout(function () {
+                    node.update(x.toUpperCase());
+                }, Math.random() * 50);
+                prompted = true;
+            }
+        });
+        if (!prompted) {
+            var s_ = JSON.stringify(res);
+            node.update(s_);
+        }
+    }
+});
+
+setTimeout(function () {
+    console.log(src);
+    console.log('---');
+    console.log(output);
+}, 200);