Inform: Language Design for Interactive Fiction

Core Idea

Inform is a specialized language for interactive fiction that abstracts computational complexity into syntax closer to narrative logic. Its design embodies specific assumptions about how stories work (objects, properties, states, actions), shaping what kinds of narratives can be created. Understanding Inform reveals how technical implementation directly constrains literary possibility.

Explainer

Inform is a programming language specifically designed for interactive fiction, but it is far more than a neutral technical tool. Its design embodies particular assumptions about how stories work—assumptions that shape what kinds of narratives are easy to create and what kinds are difficult.

Inform models narrative through objects, properties, and state changes. A story world consists of objects (rooms, items, characters) with properties (descriptions, conditions, relationships). Narrative progresses through actions that change these properties: taking an object changes its location; solving a puzzle changes a state flag; moving between rooms changes the player's location property. This model is elegant and powerful for certain kinds of narratives, particularly those involving exploration, puzzle-solving, and spatial navigation.

However, this object-property-action model shapes what narrative is natural in Inform. Stories structured around discovery and interaction with objects are straightforward. Internal monologue or psychological depth—states that are primarily conceptual rather than object-based—are more difficult to represent elegantly. Dialogue-centered or non-spatial narratives require more elaborate workarounds. A story about emotional transformation or social negotiation, while possible in Inform, may require fighting the language's affordances.

This reveals something important about the relationship between technical design and literary form. Inform is not a neutral implement; it is a tool shaped by particular assumptions. These assumptions enable certain aesthetic possibilities while constraining others. Understanding interactive fiction literature requires understanding the technical substrate—what the tool makes easy, natural, and elegant, and what it makes difficult or awkward.

Different authoring languages shape different narrative possibilities. Twine, another interactive fiction language, models story as nodes and links rather than objects and properties, enabling branching narrative in a way Inform does not. A language designed around dialogue as the primary unit would enable different narrative possibilities than Inform's object-focus. This suggests that literary form is not independent of technical implementation but emerges from it.

The broader lesson is that technical choices are aesthetic choices. Programming language design, data structure selection, and system architecture are not merely implementation details; they shape what stories can be told and how naturally they can be told. Interactive fiction authors work within the affordances and constraints of their chosen language. Understanding the works thus requires understanding the technical choices that made them possible.