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diff --git a/node_modules/fbjs/lib/UnicodeBidiDirection.js.flow b/node_modules/fbjs/lib/UnicodeBidiDirection.js.flow
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+/**
+ * Copyright (c) 2013-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @providesModule UnicodeBidiDirection
+ * @typechecks
+ * @flow
+ */
+
+/**
+ * Constants to represent text directionality
+ *
+ * Also defines a *global* direciton, to be used in bidi algorithms as a
+ * default fallback direciton, when no better direction is found or provided.
+ *
+ * NOTE: Use `setGlobalDir()`, or update `initGlobalDir()`, to set the initial
+ *       global direction value based on the application.
+ *
+ * Part of the implementation of Unicode Bidirectional Algorithm (UBA)
+ * Unicode Standard Annex #9 (UAX9)
+ * http://www.unicode.org/reports/tr9/
+ */
+
+'use strict';
+
+const invariant = require('./invariant');
+
+export type BidiDirection = 'LTR' | 'RTL' | 'NEUTRAL';
+export type HTMLDir = 'ltr' | 'rtl';
+
+const NEUTRAL = 'NEUTRAL'; // No strong direction
+const LTR = 'LTR'; // Left-to-Right direction
+const RTL = 'RTL'; // Right-to-Left direction
+
+let globalDir: ?BidiDirection = null;
+
+// == Helpers ==
+
+/**
+ * Check if a directionality value is a Strong one
+ */
+function isStrong(dir: BidiDirection): boolean {
+  return dir === LTR || dir === RTL;
+}
+
+/**
+ * Get string value to be used for `dir` HTML attribute or `direction` CSS
+ * property.
+ */
+function getHTMLDir(dir: BidiDirection): HTMLDir {
+  invariant(isStrong(dir), '`dir` must be a strong direction to be converted to HTML Direction');
+  return dir === LTR ? 'ltr' : 'rtl';
+}
+
+/**
+ * Get string value to be used for `dir` HTML attribute or `direction` CSS
+ * property, but returns null if `dir` has same value as `otherDir`.
+ * `null`.
+ */
+function getHTMLDirIfDifferent(dir: BidiDirection, otherDir: BidiDirection): ?HTMLDir {
+  invariant(isStrong(dir), '`dir` must be a strong direction to be converted to HTML Direction');
+  invariant(isStrong(otherDir), '`otherDir` must be a strong direction to be converted to HTML Direction');
+  return dir === otherDir ? null : getHTMLDir(dir);
+}
+
+// == Global Direction ==
+
+/**
+ * Set the global direction.
+ */
+function setGlobalDir(dir: BidiDirection): void {
+  globalDir = dir;
+}
+
+/**
+ * Initialize the global direction
+ */
+function initGlobalDir(): void {
+  setGlobalDir(LTR);
+}
+
+/**
+ * Get the global direction
+ */
+function getGlobalDir(): BidiDirection {
+  if (!globalDir) {
+    this.initGlobalDir();
+  }
+  invariant(globalDir, 'Global direction not set.');
+  return globalDir;
+}
+
+const UnicodeBidiDirection = {
+  // Values
+  NEUTRAL,
+  LTR,
+  RTL,
+  // Helpers
+  isStrong,
+  getHTMLDir,
+  getHTMLDirIfDifferent,
+  // Global Direction
+  setGlobalDir,
+  initGlobalDir,
+  getGlobalDir
+};
+
+module.exports = UnicodeBidiDirection;
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