Description
Look up one exact state/symbol transition and return explicit null evidence when it is undefined.
A deterministic transition maps a state and one literal alphabet symbol to at most one next state. A partial table may leave some pairs undefined; a complete table defines every state/symbol pair. Tracing one word, exploring all graph paths and changing the accepting set are distinct operations. IDs and symbols use exact string identity.
Look up one exact state/symbol transition and return explicit null evidence when it is undefined.
When to use this tool
Use a single-step lookup to inspect one exact source-state and input-symbol pair.
How to use the tool and how it works
- Enter transitionsJson, state, symbol using the definitions below. Serialize JSON text fields in the decoded shape shown below.
- Run the operation. Resolve input-format errors before interpreting an output.
- Read result.target, result.defined, using the stated boundary, ordering, sign and absence conventions.
Reject duplicate transition keys, then look for the exact [state,symbol] pair. Return its destination with defined true, or target null with defined false.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| transitionsJson | JSON array of {from,symbol,to} literal string records, preserving transition indexes. Determinism is checked or audited as described above. | Text, at most 8,192 UTF-16 code units; narrower grammar/range rules also apply. |
| state | Literal source state for one exact-key transition lookup. | Text, at most 8,192 UTF-16 code units; narrower grammar/range rules also apply. |
| symbol | Literal input symbol for one exact-key transition lookup. | Text, at most 8,192 UTF-16 code units; narrower grammar/range rules also apply. |
These decoded structures show the examples inside JSON text fields. Supply their serialized JSON strings as input.
{
"transitionsJson": [
{
"from": "a",
"symbol": "x",
"to": "b"
},
{
"from": "b",
"symbol": "x",
"to": "b"
}
]
}| Output field | Interpretation |
|---|---|
| result | Object containing the fields below. |
| result.target | Destination of the exact state/symbol key, or null if undefined. |
| result.defined | Whether the exact state/symbol key exists. |
{
"input": {
"transitionsJson": "[{\"from\": \"a\", \"symbol\": \"x\", \"to\": \"b\"}, {\"from\": \"b\", \"symbol\": \"x\", \"to\": \"b\"}]",
"state": "a",
"symbol": "x"
},
"output": {
"result": {
"target": "b",
"defined": true
}
}
}Limitations and assumptions
- No fallback, inferred alphabet or sink transition is supplied. The tool checks deterministic keys but has no separate declared-state-bank validation.
- Transition JSON is an array of {from,symbol,to} string records. Tools requiring a declared automaton use a nonempty distinct state bank and distinct alphabet, validate endpoints and symbols, and reject duplicate [from,symbol] keys. Trace-only tools validate keys without inferring a declared universe. No normalization or implicit sink is provided.
- Every declared outer field is required and unknown outer fields are rejected. Strings and JSON text have size limits, lists are bounded to 128 entries, and JSON nesting/node counts are bounded. Tighter operation-specific bounds stated above take precedence.
- Numeric outputs must remain finite and within safe-integer magnitude. Original record indexes and cell coordinates are zero-based; stated half-open ranges exclude their end.
Alternative or Complementary methods
Use endpoint and duplicate-key audits before transformations. Check completeness before complementing an accepting set, and preserve the declared alphabet, start-state convention and acceptance policy with exported tables.
References
Similar or alternative tools
- DFA First Undefined Transition Finder
Locate the first undefined step of a partial deterministic trace and retain its state and requested symbol.
- DFA Deterministic Transition Key Audit
Audit repeated deterministic state/symbol transition keys, including identical duplicate records.