Cached require in node.js

function watchedRequire(file)
{
    var fs      = require('fs');
    var path    = require('path');

    path.exists(file, function(exists) {
        if(exists)
        {
            fs.watchFile(file, function(current, previous) {
                if(current.nlink === 0) // file does not exist anymore
                {
                    delete(require.cache[file]);
                    fs.unwatchFile(file);
                    console.log('Deleted');
                    return;
                }

                if(current.mtime - previous.mtime) // has changed
                {
                    delete(require.cache[file]);
                    console.log('Changed');
                    require(file); // rebuild cache with new file immediately
                }
                // console.log(require.cache);
            });
            return require(file);
        }
        throw new Error('File not found: '+file);
    });
}

var file = watchedRequire(process.cwd()+'/file.js');