// Това ми е 'views/article/details'
{{#if user}}
  {{#ifCond user._id '===' article.authordId }}
        <a class="btn btn-success btn-xs" href="/article/edit/{{article._id}}">Edit &raquo;</a>
        <a class="btn btn-danger btn-xs" href="/article/delete/{{article._id}}">Delete &raquo;</a>
    {{/ifCond}}
    {{#if user.isAdmin}}
        <a class="btn btn-success btn-xs" href="/article/edit/{{article._id}}">Edit &raquo;</a>
        <a class="btn btn-danger btn-xs" href="/article/delete/{{article._id}}">Delete &raquo;</a>
    {{/if}}
{{/if}}

// express.js
const hbs  = require('handlebars');
const helpers = require('./../utilities/handlebars');

 app.set('views', path.normalize(path.join(__dirname, '/../views')));
 app.set('view engine', 'hbs');

 hbs.registerHelper("ifCond", helpers.ifCond);

// utilities/handlebars.js
module.exports = {
    ifCond: (v1, operator, v2, options) => {

        switch (operator) {
            case '==':
                return (v1 == v2) ? options.fn(this) : options.inverse(this);
            case '===':
                return (v1 === v2) ? options.fn(this) : options.inverse(this);
            case '!=':
                return (v1 != v2) ? options.fn(this) : options.inverse(this);
            case '!==':
                return (v1 !== v2) ? options.fn(this) : options.inverse(this);
            case '<':
                return (v1 < v2) ? options.fn(this) : options.inverse(this);
            case '<=':
                return (v1 <= v2) ? options.fn(this) : options.inverse(this);
            case '>':
                return (v1 > v2) ? options.fn(this) : options.inverse(this);
            case '>=':
                return (v1 >= v2) ? options.fn(this) : options.inverse(this);
            case '&&':
                return (v1 && v2) ? options.fn(this) : options.inverse(this);
            case '||':
                return (v1 || v2) ? options.fn(this) : options.inverse(this);
            default:
                return options.inverse(this);
        }
    }
};