calling function prototype in handlebars

Question

I built a simple app using express and handlebars

in my models, I have function prototype like this

// myModel.js
Student.prototype.getFullname = function () {
  return `${this.first_name} ${this.last_name}`;
}

in my router, I can invoke the function prototype like this

// myRouter.js
const rows = await Model.Student.findAll();
console.log(rows[0].getFullname()); // I can invoke function prototype here
res.render('mypage', rows); // with express, render it to hbs

my question: how to call a function prototype in handlebars?

{{#each this}}
<tr>
    <td>{{ id }}</td>
    <td>{{ first_name }}</td>
    <td>{{ last_name }}</td>
    <td>{{ rows[0].getFullname() }}</td> // I wanna call it here
</tr>
{{/each}}

Answer 1

In handlebars helpers docs, there's literally your example, with the fullName helper.

Registering helper:

Handlebars.registerHelper('getFullName', function(student) {

    return `${student.first_name} ${student.last_name}`;

});

Using helper:

{{#each this}}
    <tr>
      <td>{{ id }}</td>
      <td>{{ first_name }}</td>
      <td>{{ last_name }}</td>
      <td>{{ getFullName this }}</td>
    </tr>
{{/each}}