javascript - path.join not working in express 3 with node v0.10.41 -

i'm trying use less express 3 getting error

"typeerror: arguments path.join must strings"

in node v0.10.41

in application code:

app.use(less({    src : path.join(__dirname, 'public', 'less'),    dest : path.join(__dirname, 'public', 'css'),    prefix : '/css' })); 

here package.json

{   "name": "tolga",   "version": "0.0.1",   "private": true,   "scripts": {     "start": "node app.js"   },   "engines": {     "node": "0.10.41",     "npm": "1.4.29"   },   "dependencies": {     "async": "~0.2.9",     "bignum": "~0.6.1",     "body-parser": "^1.14.2",     "connect-redis": "~1.4.5",     "ejs": "*",     "express": "3.2.6",     "geolib": "~1.3.1"   } } 

the error stems use of less module middleware.

the appropriate approach utilize less-middleware module. once installed, can use middleware in manner:

// install 'less-middleware' module first var lessmiddleware = require('less-middleware);  // 'less-middleware' takes source first argument. app.use(lessmiddleware(path.join(__dirname, 'public'), {   dest: path.join(__dirname, 'public', 'css'),   prefix: '/css' }));