How to specify file order with Grunt?

I've just started using Grunt, and I'm trying to get the concat task to concat my files in a specific order. Here's what I've got:

module.exports = function(grunt) {
    grunt.initConfig({
        pkg: grunt.file.readJSON('package.json'),
        concat: {
            options: {
                separator: ';'
            },
            dist: {
                src: ['www/js/*.js','www/js/main.js','!**/*.{min,pack}.js','!<%= concat.dist.dest %>','!<%= uglify.dist %>'],
                dest: 'www/js/<%= pkg.name %>.js'
            }
        },

I was hoping that by putting www/js/main.js second, it would move the file down to the bottom of the list, but that doesn't appear to be the case.

How can I impose some order on the list of files it matches?

Your problem is that main.js is matched by the first pattern so the second pattern is made redundant. This might seem like a hacky way of doing it but basically you have to exclude it from the first pattern before you include it in the second; like so:

    concat: {
        options: {
            separator: ';'
        },
        dist: {
            src: ['www/js/*.js', '!www/js/main.js', 'www/js/main.js','!**/*.{min,pack}.js','!<%= concat.dist.dest %>','!<%= uglify.dist %>'],
            dest: 'www/js/<%= pkg.name %>.js'
        }
    }

Note that when using minimatch pattern order is important.