Output path comparison

Parsing nix-env's performance statistics failed.

Parse error:
Error("expected value", line: 1, column: 1)

Evaluation output:
warning: ignoring the user-specified setting 'restrict-eval', because it is a restricted setting and you are not a trusted user
{
  "cpuTime": 246.114,
  "envs": {
    "number": 130928935,
    "elements": 199508567,
    "bytes": 3690931496
  },
  "list": {
    "elements": 930886918,
    "bytes": 7447095344,
    "concats": 9989205
  },
  "values": {
    "number": 271640768,
    "bytes": 6519378432
  },
  "symbols": {
    "number": 384086,
    "bytes": 17891492
  },
  "sets": {
    "number": 33630495,
    "bytes": 9216996816,
    "elements": 372831369
  },
  "sizes": {
    "Env": 16,
    "Value": 24,
    "Bindings": 8,
    "Attr": 24
  },
  "nrOpUpdates": 16120019,
  "nrOpUpdateValuesCopied": 273841229,
  "nrThunks": 190459533,
  "nrAvoided": 183280478,
  "nrLookups": 97132032,
  "nrPrimOpCalls": 79068893,
  "nrFunctionCalls": 115388907,
  "gc": {
    "heapSize": 13407019008,
    "totalBytes": 33191418928
  }
}