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node_modules/vant/lib/utils/dom/raf.js

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+"use strict";
+
+exports.__esModule = true;
+exports.raf = raf;
+exports.doubleRaf = doubleRaf;
+exports.cancelRaf = cancelRaf;
+
+var _ = require("..");
+
+/**
+ * requestAnimationFrame polyfill
+ */
+var prev = Date.now();
+/* istanbul ignore next */
+
+function fallback(fn) {
+  var curr = Date.now();
+  var ms = Math.max(0, 16 - (curr - prev));
+  var id = setTimeout(fn, ms);
+  prev = curr + ms;
+  return id;
+}
+/* istanbul ignore next */
+
+
+var root = _.isServer ? global : window;
+/* istanbul ignore next */
+
+var iRaf = root.requestAnimationFrame || fallback;
+/* istanbul ignore next */
+
+var iCancel = root.cancelAnimationFrame || root.clearTimeout;
+
+function raf(fn) {
+  return iRaf.call(root, fn);
+} // double raf for animation
+
+
+function doubleRaf(fn) {
+  raf(function () {
+    raf(fn);
+  });
+}
+
+function cancelRaf(id) {
+  iCancel.call(root, id);
+}