menu.bemhtml

block('b-menu')(
    tag()('ul'),
    elem('item').tag()('li'),
    elem('text').tag()('span')
)

menu.bemjson.js

{
            block: 'b-menu',
            content: [
                {
                    text: 'One',
                    current: true,
                    submenu: true
                },
                {
                    text: 'Two'
                },
                {
                    text: 'Three'
                }
            ].map(function(item){
                var submenu = {
                    block: 'b-submenu',
                    mix: {block: 'b-menu', elem: 'submenu'},
                    content: 'Submenu here...'
                };
                var block = {
                    elem: 'item',
                    mods: {current: item.current || '', submenu: item.submenu || ''},
                    content: [
                        {
                            elem: 'text',
                            content: item.text || ''
                        },
                        item.submenu ? submenu : ''
                    ]
                };
                return block;
            })
        }