path.join([path1], [path2], [...])

path.join('/foo', 'bar', 'baz/asdf', 'quux', '..') // returns '/foo/bar/baz/asdf' path.join('foo', {}, 'bar') // throws exception TypeError: Arguments to path.join must be strings

// windows version   exports.join = function() {     function f(p) {       if (!util.isString(p)) {         throw new TypeError('Arguments to path.join must be strings');       }       return p;     }       var paths = Array.prototype.filter.call(arguments, f);     var joined = paths.join('\\');       // Make sure that the joined path doesn't start with two slashes, because     // normalize() will mistake it for an UNC path then.     //     // This step is skipped when it is very clear that the user actually     // intended to point at an UNC path. This is assumed when the first     // non-empty string arguments starts with exactly two slashes followed by     // at least one more non-slash character.     //     // Note that for normalize() to treat a path as an UNC path it needs to     // have at least 2 components, so we don't filter for that here.     // This means that the user can use join to construct UNC paths from     // a server name and a share name; for example:     // path.join('//server', 'share') -> '\\\\server\\share\')     if (!/^[\\\/]{2}[^\\\/]/.test(paths[0])) {       joined = joined.replace(/^[\\\/]{2,}/, '\\');     }       return exports.normalize(joined);   };