HTMLi

HTMLi is a hypothetical markup extension intended to add declarative, data-driven rendering to HTML through a small set of special attributes. It is not an official standard and remains primarily discussed in theoretical or experimental contexts.

The design goal of HTMLi is to enable conditional rendering, iteration, and data binding directly in markup, while preserving the human readability of HTML and avoiding heavy JavaScript boilerplate. Proponents emphasize progressive enhancement, accessibility, and compatibility with existing HTML semantics.

Core features are expressed through attributes prefixed with i-. Examples include i-if for conditional rendering, i-for for looping over a collection, i-bind for inserting expression results into text or attributes, and i-model for basic two-way form binding. These attributes are intended to be declarative and non-intrusive, letting developers describe UI state without inline scripting.

Because HTMLi has no native engine in current browsers, implementations exist as preprocessors, transpilers, or runtime libraries that transform HTMLi documents into standard HTML and JavaScript before delivery. Such tools may integrate with build pipelines or operate in the client at runtime, converting i- constructs into DOM operations.

Adoption of HTMLi has been limited, with no consensus standard or wide browser support. Critics point to potential tooling fragmentation, performance considerations, and the risk of duplicating capabilities already provided by modern frameworks. Support is typically framed as experimental or educational, useful for exploring declarative approaches but not yet suitable for production-wide use.

Example: <div i-if="user.loggedIn" i-bind="user.name">Hello, {{user.name}}!</div> would render when user.loggedIn is true and display the bound name. See also HTML, templating, and web components.