calculator.json

{
  "id": "calculator",
  "name": "Calculator",
  "version": "1.0.0",
  "description": "Safe math expression evaluator. Supports arithmetic, powers, roots, trig, logarithms, and constants (pi, e, inf). Uses Python's ast module — no eval() security risks.",
  "author": "Chris4K",
  "tags": [
    "math",
    "utility",
    "calculator",
    "safe-eval"
  ],
  "dependencies": [],
  "schema": {
    "input": {
      "expression": "str — math expression, e.g. 'sqrt(144) + 2**8 - pi'"
    },
    "output": {
      "result": "float",
      "expression": "str",
      "formatted": "str"
    }
  },
  "code": "import ast\nimport math\nimport operator\n\n# Whitelist of safe operators\n_OPERATORS = {\n    ast.Add: operator.add,\n    ast.Sub: operator.sub,\n    ast.Mult: operator.mul,\n    ast.Div: operator.truediv,\n    ast.Pow: operator.pow,\n    ast.USub: operator.neg,\n    ast.UAdd: operator.pos,\n    ast.Mod: operator.mod,\n    ast.FloorDiv: operator.floordiv,\n}\n\n# Whitelist of safe functions and constants\n_SAFE_NAMES = {\n    \"pi\": math.pi,\n    \"e\": math.e,\n    \"inf\": math.inf,\n    \"tau\": math.tau,\n    \"sqrt\": math.sqrt,\n    \"cbrt\": lambda x: x ** (1 / 3),\n    \"abs\": abs,\n    \"round\": round,\n    \"floor\": math.floor,\n    \"ceil\": math.ceil,\n    \"log\": math.log,\n    \"log2\": math.log2,\n    \"log10\": math.log10,\n    \"exp\": math.exp,\n    \"sin\": math.sin,\n    \"cos\": math.cos,\n    \"tan\": math.tan,\n    \"asin\": math.asin,\n    \"acos\": math.acos,\n    \"atan\": math.atan,\n    \"atan2\": math.atan2,\n    \"degrees\": math.degrees,\n    \"radians\": math.radians,\n    \"hypot\": math.hypot,\n    \"factorial\": math.factorial,\n    \"gcd\": math.gcd,\n    \"min\": min,\n    \"max\": max,\n    \"sum\": sum,\n    \"pow\": pow,\n}\n\n\ndef _eval_node(node):\n    if isinstance(node, ast.Constant):\n        if isinstance(node.value, (int, float, complex)):\n            return node.value\n        raise ValueError(f\"Unsupported constant: {node.value!r}\")\n    elif isinstance(node, ast.BinOp):\n        op = _OPERATORS.get(type(node.op))\n        if op is None:\n            raise ValueError(f\"Unsupported operator: {type(node.op).__name__}\")\n        return op(_eval_node(node.left), _eval_node(node.right))\n    elif isinstance(node, ast.UnaryOp):\n        op = _OPERATORS.get(type(node.op))\n        if op is None:\n            raise ValueError(f\"Unsupported unary op: {type(node.op).__name__}\")\n        return op(_eval_node(node.operand))\n    elif isinstance(node, ast.Call):\n        if not isinstance(node.func, ast.Name):\n            raise ValueError(\"Only simple function calls allowed\")\n        fname = node.func.id\n        if fname not in _SAFE_NAMES:\n            raise ValueError(f\"Function not allowed: {fname!r}\")\n        args = [_eval_node(a) for a in node.args]\n        return _SAFE_NAMES[fname](*args)\n    elif isinstance(node, ast.Name):\n        if node.id not in _SAFE_NAMES:\n            raise ValueError(f\"Name not allowed: {node.id!r}\")\n        return _SAFE_NAMES[node.id]\n    elif isinstance(node, ast.Expression):\n        return _eval_node(node.body)\n    else:\n        raise ValueError(f\"Unsupported AST node: {type(node).__name__}\")\n\n\ndef execute(expression: str) -> dict:\n    \"\"\"Safely evaluate a mathematical expression.\"\"\"\n    if not expression or not expression.strip():\n        return {\"error\": \"Expression cannot be empty\"}\n    try:\n        tree = ast.parse(expression.strip(), mode=\"eval\")\n        result = _eval_node(tree)\n        if isinstance(result, float) and result.is_integer() and abs(result) < 1e15:\n            formatted = str(int(result))\n        else:\n            formatted = f\"{result:.10g}\"\n        return {\n            \"expression\": expression,\n            \"result\": float(result) if not isinstance(result, complex) else None,\n            \"formatted\": formatted,\n        }\n    except ZeroDivisionError:\n        return {\"error\": \"Division by zero\", \"expression\": expression}\n    except Exception as exc:\n        return {\"error\": str(exc), \"expression\": expression}\n",
  "downloads": 1,
  "created_at": 1710000002
}