Source: apc-abstract/lib/string/to_katakana.js

/**
 * Convert a string into katakana.
 * @function lib.string.toKatakana
 * @param {string} str - String to convert.
 * @returns {string} - Katakana string.
 * @author Taka Okunishi
 *
 */
var _patterns = require('./_patterns');
module.exports = function (str) {
    return str && str.replace(_patterns.HIRAGANA, function ($0) {
        return String.fromCharCode($0.charCodeAt(0) + 0x60);
    });
};