Glossary

These are the terms the ReActionView docs use. Terms that belong to the template language, such as state, slot, key and action, are defined in the Herb glossary.

Client

The JavaScript that runs in the browser, loaded with import "reactionview". It finds the slots in the page, holds the states, runs actions and asks the server for what it cannot build itself. See JavaScript Client.

Debug mode

The setting that marks each element with the template and ERB tag it came from, and loads the dev tools. See Debug Mode.

Dev server

The Herb dev server, started inside your Rails server in development when config.slots is on. It watches your templates and updates open pages when one changes. See Development Tools.

Dev tools

The Herb badge and panel in the top right corner of a page in development. It shows what Herb reported about the page and which template rendered what.

Intercepting

Handing .html.erb templates to ReActionView, turned on with config.intercept_erb. On Rails 8.2 that takes them from Rails' own Herb implementation, and on earlier versions from Rails' ERB handler. See Rails Integration.

Mode

Whether a template's unrendered branches are built by the server or the browser, set with <%# herb:slots server %> or <%# herb:slots client %>. See Server and Client Rendering.

Optimistic row

The row a form with data-herb-into adds to a list before the server has answered. See Collections and Forms.

Slots format

The slots request format, with the MIME type application/vnd.herb.slots+json, that the client uses to ask your controllers for a page's values. See Rails Integration.

Validation mode

What happens when a validator finds a problem in a template, set with config.validation_mode. See Validation Overlays.

Values request

A request in the slots format. It carries the browser's states in a Herb-State header, runs your controller action as usual, and answers with the values that changed instead of HTML. Your controller reads the states with herb_state.