grunt-task lazyloading

Gruntfile.js

module.exports = function (grunt) {
    grunt.initConfig({
        // as usual, just make sure that – for multitasks – there always needs to be 
        // an `options`-entry to correctly detect them
        copy: {
            options: {},
            dist: {
                files: [{
                    // ....
                }]
            }
        }
    });
    
    // registers task-placeholders that will load the npm-tasks when they are actually invoked.
    grunt.registerNpmTasks = function(tasksMap) {
        Object.keys(tasksMap).forEach(function(taskName) {
            var cfg = grunt.config(taskName),
                isMultiTask = false;

            grunt.verbose.write('[lazyload] '+taskName.underline+' ('+tasksMap[taskName].yellow+')...');

            if(!cfg) {
                grunt.verbose.fail('no config');
                return;
            }

            if(cfg.options) { isMultiTask = true; }

            grunt.verbose.ok();
            grunt[isMultiTask? 'registerMultiTask' : 'registerTask'](taskName, function() {
                grunt.verbose.writeln('[lazyload] invocation for task '+taskName.underline+', target »'+this.target+'«. Will load module: '+tasksMap[taskName].yellow+'.');
                grunt.loadNpmTasks(tasksMap[taskName]);

                if(isMultiTask || this.target) {
                    grunt.task.run(taskName + ':' + this.target);
                } else {
                    grunt.task.run(taskName);
                }
            });
        });
    };
    
    // maps task-names to npm-module-names and registers the placeholders
    grunt.registerNpmTasks({
        'uglify': 'grunt-contrib-uglify',
        'copy': 'grunt-contrib-copy',
        'concat': 'grunt-contrib-concat',
        'cssmin': 'grunt-contrib-cssmin'
    });
};