FSM Maker

Purpose & User Intent: The FSM Maker is a domain tool for designers, developers, educators, and researchers to model, validate, and communicate finite state machines. It solves the problem of documenting states, the transition function, and acceptance criteria, while enabling portability of models for analysis, teaching, and collaboration. Typical users include compiler engineers designing lexical analyzers, protocol designers modeling stateful handshakes, UI/state machine logic for applications, and educators illustrating automata concepts. When to use: during design and analysis phases to verify behavior before implementation and to share formal models with team members.

Core Logic & Features: The tool manages a formal FSM model comprising a states set, an input alphabet, a transition function, a start state, and a set of final states. Required features include declaring at least one state, an alphabet, a start state, and a complete transition mapping for deterministic use; optional/advanced features cover epsilon transitions, nondeterministic mappings, multiple submachines, and NFA-to-DFA conversion. Validation routines detect missing transitions for required inputs, undefined states, unreachable states, or conflicting mappings. Core capabilities include grouped input modeling, determinism verification, simulation traces, and export options such as Mermaid, DOT, or JSON. A key differentiator is formal model validation aligned with teaching, research, and integration workflows.

Inputs & Outputs: Inputs include: states (array of strings), alphabet (array of strings), start_state (string), final_states (array), transitions (array of objects {from, on, to}) with strict typing. Sample: states=[S0,S1,S2], alphabet=[a,b], start_state=S0, final_states=[S2], transitions=[{from:S0,on:a,to:S1},{from:S1,on:b,to:S2},{from:S2,on:a,to:S0}]. Outputs are a visually rendered SVG diagram and machine-readable exports (Mermaid, DOT, JSON). Formatting rules preserve exact state identifiers and export in canonical order when possible.

Algorithms & Calculations: Determinism checks ensure a (state, symbol) pair maps to at most one next state. Reachability uses graph traversal from the start state to identify accessible states. Optional: DFA minimization to produce a smallest equivalent machine; NFA-to-DFA conversion to standardize representations. Simulation can produce traces given an input word. Exports reflect the underlying model faithfully in diagram and text form.

Error & Edge Cases: Missing start state, transitions referencing unknown states, or undefined symbols trigger validation errors. Non-deterministic mappings raise determinism warnings when required. Incomplete transition coverage can produce dead-state semantics or warnings depending on mode. External data unavailability is treated as input errors requiring correction.

Industry/Region & Localization: Terminology follows standard automata nomenclature; ASCII identifiers are assumed. Exports support integration with international documentation workflows; no locale-specific formatting is mandated. Localization hooks exist for future translations but core model semantics remain language-agnostic.

Assumptions & Exclusions: Assumes a finite, explicitly defined state set and a finite alphabet. Runtime event-driven semantics, probabilistic transitions, or weighted edges are out of scope. This spec excludes UI, storage, and deployment details; focuses on formal modeling, validation, and export capabilities.