{
  "machine": "ε-NFA",
  "sigma": [
    "d",
    ".",
    "+",
    "-"
  ],
  "states": [
    {
      "id": "s1",
      "x": 110,
      "y": 260,
      "name": "start"
    },
    {
      "id": "s2",
      "x": 300,
      "y": 260,
      "name": "signed"
    },
    {
      "id": "s3",
      "x": 490,
      "y": 260,
      "name": "integer"
    },
    {
      "id": "s4",
      "x": 680,
      "y": 260,
      "name": "point"
    },
    {
      "id": "s5",
      "x": 870,
      "y": 260,
      "name": "fraction"
    }
  ],
  "startId": "s1",
  "accepts": [
    "s3",
    "s5"
  ],
  "transitions": [
    {
      "id": "t1",
      "from": "s1",
      "to": "s2",
      "symbol": "+"
    },
    {
      "id": "t2",
      "from": "s1",
      "to": "s2",
      "symbol": "-"
    },
    {
      "id": "t3",
      "from": "s1",
      "to": "s2",
      "symbol": "ε"
    },
    {
      "id": "t4",
      "from": "s2",
      "to": "s3",
      "symbol": "d"
    },
    {
      "id": "t5",
      "from": "s3",
      "to": "s3",
      "symbol": "d"
    },
    {
      "id": "t6",
      "from": "s3",
      "to": "s4",
      "symbol": "."
    },
    {
      "id": "t7",
      "from": "s4",
      "to": "s5",
      "symbol": "d"
    },
    {
      "id": "t8",
      "from": "s5",
      "to": "s5",
      "symbol": "d"
    }
  ],
  "notes": [
    {
      "id": "n1",
      "x": 110,
      "y": 70,
      "color": "blue",
      "anchorStates": [],
      "anchorTransitions": [],
      "text": "The float-literal regex [+-]?d+(.d+)? compiled to states (d = any digit). The ε edge silently skips the optional sign; the decimal branch only opens after at least one digit. This is Thompson construction — the machinery inside every regex engine."
    },
    {
      "id": "n2",
      "x": 110,
      "y": 400,
      "color": "green",
      "anchorStates": [],
      "anchorTransitions": [],
      "text": "Step through dd.dd and watch the ε-closure fire before any input is read. d. and .dd both fail — each for a different reason."
    }
  ],
  "meta": {
    "title": "Float regex, compiled",
    "blurb": "The regex [+-]?d+(.d+)? as an ε-NFA, where d stands for any digit — what a regex engine actually builds. ε-jumps make the sign optional; the fraction needs a digit after the dot.",
    "inputs": [
      {
        "w": "dd",
        "expect": "accept",
        "label": "like 42"
      },
      {
        "w": "+ddd",
        "expect": "accept",
        "label": "like +314"
      },
      {
        "w": "dd.dd",
        "expect": "accept",
        "label": "like 31.41"
      },
      {
        "w": "-d.d",
        "expect": "accept",
        "label": "like -2.5"
      },
      {
        "w": "d.",
        "expect": "reject",
        "label": "trailing dot"
      },
      {
        "w": ".dd",
        "expect": "reject",
        "label": "no integer part"
      }
    ],
    "library": {
      "author": {
        "login": "thethinkmachine"
      },
      "license": "CC-BY-4.0",
      "tags": [
        "showcase",
        "nfa"
      ],
      "difficulty": "intermediate"
    }
  },
  "format": "automata-studio/workspace",
  "schema": 1,
  "app": "dev"
}