grunt Warning Task "watch" not found

Question

Gruntfile.js:

grunt.initConfig({
 watch: {
  compass: {
    files: [
      'app/styles/**/*.{scss,sass}'
    ],
    tasks: 'compass reload'
  },
.....
grunt.registerTask('dev', 'watch');

when i run

grunt dev 

i get the error

Warning: Task "watch" not found. Use --force to continue. 

I use grunt-cli v0.1.6 and grunt v0.4.0, grunt-contrib-watch is installed.

Answer 1

You don't have to install the whole contrib-package. There is a separate one for watch

npm install grunt-contrib-watch --save-dev

and at the end:

grunt.loadNpmTasks('grunt-contrib-watch');

Answer 2

Well.

npm install grunt-contrib --save-dev

and add this line before the last line of grunt.js:

grunt.loadNpmTasks('grunt-contrib');

Also, i had to have Ruby installed...