{
 "language": "Solidity",
 "sources": {
  "a.sol": {
   "content": "// SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0;\ncontract A { uint256 immutable x = 1 + 3; function f() public pure returns (uint256) { return x; } }"
  }
 },
 "settings": {
  "evmVersion": "petersburg",
  "outputSelection": {
   "*": {
    "A": [
     "evm.deployedBytecode.immutableReferences"
    ]
   }
  }
 }
}