{
  "type": "Script",
  "span": {
    "start": 63,
    "end": 841,
    "ctxt": 0
  },
  "body": [
    {
      "type": "TsInterfaceDeclaration",
      "span": {
        "start": 63,
        "end": 94,
        "ctxt": 0
      },
      "id": {
        "type": "Identifier",
        "span": {
          "start": 73,
          "end": 77,
          "ctxt": 0
        },
        "value": "Base",
        "optional": false
      },
      "declare": false,
      "typeParams": null,
      "extends": [],
      "body": {
        "type": "TsInterfaceBody",
        "span": {
          "start": 78,
          "end": 94,
          "ctxt": 0
        },
        "body": [
          {
            "type": "TsPropertySignature",
            "span": {
              "start": 80,
              "end": 92,
              "ctxt": 0
            },
            "readonly": false,
            "key": {
              "type": "Identifier",
              "span": {
                "start": 80,
                "end": 83,
                "ctxt": 0
              },
              "value": "foo",
              "optional": false
            },
            "computed": false,
            "optional": false,
            "init": null,
            "params": [],
            "typeAnnotation": {
              "type": "TsTypeAnnotation",
              "span": {
                "start": 83,
                "end": 91,
                "ctxt": 0
              },
              "typeAnnotation": {
                "type": "TsKeywordType",
                "span": {
                  "start": 85,
                  "end": 91,
                  "ctxt": 0
                },
                "kind": "string"
              }
            },
            "typeParams": null
          }
        ]
      }
    },
    {
      "type": "TsInterfaceDeclaration",
      "span": {
        "start": 95,
        "end": 142,
        "ctxt": 0
      },
      "id": {
        "type": "Identifier",
        "span": {
          "start": 105,
          "end": 112,
          "ctxt": 0
        },
        "value": "Derived",
        "optional": false
      },
      "declare": false,
      "typeParams": null,
      "extends": [
        {
          "type": "TsExpressionWithTypeArguments",
          "span": {
            "start": 121,
            "end": 125,
            "ctxt": 0
          },
          "expression": {
            "type": "Identifier",
            "span": {
              "start": 121,
              "end": 125,
              "ctxt": 0
            },
            "value": "Base",
            "optional": false
          },
          "typeArguments": null
        }
      ],
      "body": {
        "type": "TsInterfaceBody",
        "span": {
          "start": 126,
          "end": 142,
          "ctxt": 0
        },
        "body": [
          {
            "type": "TsPropertySignature",
            "span": {
              "start": 128,
              "end": 140,
              "ctxt": 0
            },
            "readonly": false,
            "key": {
              "type": "Identifier",
              "span": {
                "start": 128,
                "end": 131,
                "ctxt": 0
              },
              "value": "bar",
              "optional": false
            },
            "computed": false,
            "optional": false,
            "init": null,
            "params": [],
            "typeAnnotation": {
              "type": "TsTypeAnnotation",
              "span": {
                "start": 131,
                "end": 139,
                "ctxt": 0
              },
              "typeAnnotation": {
                "type": "TsKeywordType",
                "span": {
                  "start": 133,
                  "end": 139,
                  "ctxt": 0
                },
                "kind": "string"
              }
            },
            "typeParams": null
          }
        ]
      }
    },
    {
      "type": "TsInterfaceDeclaration",
      "span": {
        "start": 143,
        "end": 194,
        "ctxt": 0
      },
      "id": {
        "type": "Identifier",
        "span": {
          "start": 153,
          "end": 161,
          "ctxt": 0
        },
        "value": "Derived2",
        "optional": false
      },
      "declare": false,
      "typeParams": null,
      "extends": [
        {
          "type": "TsExpressionWithTypeArguments",
          "span": {
            "start": 170,
            "end": 177,
            "ctxt": 0
          },
          "expression": {
            "type": "Identifier",
            "span": {
              "start": 170,
              "end": 177,
              "ctxt": 0
            },
            "value": "Derived",
            "optional": false
          },
          "typeArguments": null
        }
      ],
      "body": {
        "type": "TsInterfaceBody",
        "span": {
          "start": 178,
          "end": 194,
          "ctxt": 0
        },
        "body": [
          {
            "type": "TsPropertySignature",
            "span": {
              "start": 180,
              "end": 192,
              "ctxt": 0
            },
            "readonly": false,
            "key": {
              "type": "Identifier",
              "span": {
                "start": 180,
                "end": 183,
                "ctxt": 0
              },
              "value": "baz",
              "optional": false
            },
            "computed": false,
            "optional": false,
            "init": null,
            "params": [],
            "typeAnnotation": {
              "type": "TsTypeAnnotation",
              "span": {
                "start": 183,
                "end": 191,
                "ctxt": 0
              },
              "typeAnnotation": {
                "type": "TsKeywordType",
                "span": {
                  "start": 185,
                  "end": 191,
                  "ctxt": 0
                },
                "kind": "string"
              }
            },
            "typeParams": null
          }
        ]
      }
    },
    {
      "type": "ClassDeclaration",
      "identifier": {
        "type": "Identifier",
        "span": {
          "start": 202,
          "end": 203,
          "ctxt": 0
        },
        "value": "A",
        "optional": false
      },
      "declare": false,
      "span": {
        "start": 196,
        "end": 230,
        "ctxt": 0
      },
      "decorators": [],
      "body": [
        {
          "type": "TsIndexSignature",
          "params": [
            {
              "type": "Identifier",
              "span": {
                "start": 211,
                "end": 220,
                "ctxt": 0
              },
              "value": "x",
              "optional": false,
              "typeAnnotation": {
                "type": "TsTypeAnnotation",
                "span": {
                  "start": 212,
                  "end": 220,
                  "ctxt": 0
                },
                "typeAnnotation": {
                  "type": "TsKeywordType",
                  "span": {
                    "start": 214,
                    "end": 220,
                    "ctxt": 0
                  },
                  "kind": "number"
                }
              }
            }
          ],
          "typeAnnotation": {
            "type": "TsTypeAnnotation",
            "span": {
              "start": 221,
              "end": 227,
              "ctxt": 0
            },
            "typeAnnotation": {
              "type": "TsTypeReference",
              "span": {
                "start": 223,
                "end": 227,
                "ctxt": 0
              },
              "typeName": {
                "type": "Identifier",
                "span": {
                  "start": 223,
                  "end": 227,
                  "ctxt": 0
                },
                "value": "Base",
                "optional": false
              },
              "typeParams": null
            }
          },
          "readonly": false,
          "static": false,
          "span": {
            "start": 210,
            "end": 228,
            "ctxt": 0
          }
        }
      ],
      "superClass": null,
      "isAbstract": false,
      "typeParams": null,
      "superTypeParams": null,
      "implements": []
    },
    {
      "type": "VariableDeclaration",
      "span": {
        "start": 232,
        "end": 241,
        "ctxt": 0
      },
      "kind": "var",
      "declare": false,
      "declarations": [
        {
          "type": "VariableDeclarator",
          "span": {
            "start": 236,
            "end": 240,
            "ctxt": 0
          },
          "id": {
            "type": "Identifier",
            "span": {
              "start": 236,
              "end": 237,
              "ctxt": 0
            },
            "value": "a",
            "optional": false,
            "typeAnnotation": {
              "type": "TsTypeAnnotation",
              "span": {
                "start": 237,
                "end": 240,
                "ctxt": 0
              },
              "typeAnnotation": {
                "type": "TsTypeReference",
                "span": {
                  "start": 239,
                  "end": 240,
                  "ctxt": 0
                },
                "typeName": {
                  "type": "Identifier",
                  "span": {
                    "start": 239,
                    "end": 240,
                    "ctxt": 0
                  },
                  "value": "A",
                  "optional": false
                },
                "typeParams": null
              }
            }
          },
          "init": null,
          "definite": false
        }
      ]
    },
    {
      "type": "VariableDeclaration",
      "span": {
        "start": 242,
        "end": 274,
        "ctxt": 0
      },
      "kind": "var",
      "declare": false,
      "declarations": [
        {
          "type": "VariableDeclarator",
          "span": {
            "start": 246,
            "end": 274,
            "ctxt": 0
          },
          "id": {
            "type": "Identifier",
            "span": {
              "start": 246,
              "end": 247,
              "ctxt": 0
            },
            "value": "b",
            "optional": false,
            "typeAnnotation": {
              "type": "TsTypeAnnotation",
              "span": {
                "start": 247,
                "end": 274,
                "ctxt": 0
              },
              "typeAnnotation": {
                "type": "TsTypeLiteral",
                "span": {
                  "start": 249,
                  "end": 274,
                  "ctxt": 0
                },
                "members": [
                  {
                    "type": "TsIndexSignature",
                    "params": [
                      {
                        "type": "Identifier",
                        "span": {
                          "start": 252,
                          "end": 261,
                          "ctxt": 0
                        },
                        "value": "x",
                        "optional": false,
                        "typeAnnotation": {
                          "type": "TsTypeAnnotation",
                          "span": {
                            "start": 253,
                            "end": 261,
                            "ctxt": 0
                          },
                          "typeAnnotation": {
                            "type": "TsKeywordType",
                            "span": {
                              "start": 255,
                              "end": 261,
                              "ctxt": 0
                            },
                            "kind": "number"
                          }
                        }
                      }
                    ],
                    "typeAnnotation": {
                      "type": "TsTypeAnnotation",
                      "span": {
                        "start": 262,
                        "end": 271,
                        "ctxt": 0
                      },
                      "typeAnnotation": {
                        "type": "TsTypeReference",
                        "span": {
                          "start": 264,
                          "end": 271,
                          "ctxt": 0
                        },
                        "typeName": {
                          "type": "Identifier",
                          "span": {
                            "start": 264,
                            "end": 271,
                            "ctxt": 0
                          },
                          "value": "Derived",
                          "optional": false
                        },
                        "typeParams": null
                      }
                    },
                    "readonly": false,
                    "static": false,
                    "span": {
                      "start": 251,
                      "end": 272,
                      "ctxt": 0
                    }
                  }
                ]
              }
            }
          },
          "init": null,
          "definite": false
        }
      ]
    },
    {
      "type": "ExpressionStatement",
      "span": {
        "start": 275,
        "end": 281,
        "ctxt": 0
      },
      "expression": {
        "type": "AssignmentExpression",
        "span": {
          "start": 275,
          "end": 280,
          "ctxt": 0
        },
        "operator": "=",
        "left": {
          "type": "Identifier",
          "span": {
            "start": 275,
            "end": 276,
            "ctxt": 0
          },
          "value": "a",
          "optional": false,
          "typeAnnotation": null
        },
        "right": {
          "type": "Identifier",
          "span": {
            "start": 279,
            "end": 280,
            "ctxt": 0
          },
          "value": "b",
          "optional": false
        }
      }
    },
    {
      "type": "ExpressionStatement",
      "span": {
        "start": 282,
        "end": 288,
        "ctxt": 0
      },
      "expression": {
        "type": "AssignmentExpression",
        "span": {
          "start": 282,
          "end": 287,
          "ctxt": 0
        },
        "operator": "=",
        "left": {
          "type": "Identifier",
          "span": {
            "start": 282,
            "end": 283,
            "ctxt": 0
          },
          "value": "b",
          "optional": false,
          "typeAnnotation": null
        },
        "right": {
          "type": "Identifier",
          "span": {
            "start": 286,
            "end": 287,
            "ctxt": 0
          },
          "value": "a",
          "optional": false
        }
      }
    },
    {
      "type": "VariableDeclaration",
      "span": {
        "start": 299,
        "end": 333,
        "ctxt": 0
      },
      "kind": "var",
      "declare": false,
      "declarations": [
        {
          "type": "VariableDeclarator",
          "span": {
            "start": 303,
            "end": 333,
            "ctxt": 0
          },
          "id": {
            "type": "Identifier",
            "span": {
              "start": 303,
              "end": 305,
              "ctxt": 0
            },
            "value": "b2",
            "optional": false,
            "typeAnnotation": {
              "type": "TsTypeAnnotation",
              "span": {
                "start": 305,
                "end": 333,
                "ctxt": 0
              },
              "typeAnnotation": {
                "type": "TsTypeLiteral",
                "span": {
                  "start": 307,
                  "end": 333,
                  "ctxt": 0
                },
                "members": [
                  {
                    "type": "TsIndexSignature",
                    "params": [
                      {
                        "type": "Identifier",
                        "span": {
                          "start": 310,
                          "end": 319,
                          "ctxt": 0
                        },
                        "value": "x",
                        "optional": false,
                        "typeAnnotation": {
                          "type": "TsTypeAnnotation",
                          "span": {
                            "start": 311,
                            "end": 319,
                            "ctxt": 0
                          },
                          "typeAnnotation": {
                            "type": "TsKeywordType",
                            "span": {
                              "start": 313,
                              "end": 319,
                              "ctxt": 0
                            },
                            "kind": "number"
                          }
                        }
                      }
                    ],
                    "typeAnnotation": {
                      "type": "TsTypeAnnotation",
                      "span": {
                        "start": 320,
                        "end": 330,
                        "ctxt": 0
                      },
                      "typeAnnotation": {
                        "type": "TsTypeReference",
                        "span": {
                          "start": 322,
                          "end": 330,
                          "ctxt": 0
                        },
                        "typeName": {
                          "type": "Identifier",
                          "span": {
                            "start": 322,
                            "end": 330,
                            "ctxt": 0
                          },
                          "value": "Derived2",
                          "optional": false
                        },
                        "typeParams": null
                      }
                    },
                    "readonly": false,
                    "static": false,
                    "span": {
                      "start": 309,
                      "end": 331,
                      "ctxt": 0
                    }
                  }
                ]
              }
            }
          },
          "init": null,
          "definite": false
        }
      ]
    },
    {
      "type": "ExpressionStatement",
      "span": {
        "start": 334,
        "end": 341,
        "ctxt": 0
      },
      "expression": {
        "type": "AssignmentExpression",
        "span": {
          "start": 334,
          "end": 340,
          "ctxt": 0
        },
        "operator": "=",
        "left": {
          "type": "Identifier",
          "span": {
            "start": 334,
            "end": 335,
            "ctxt": 0
          },
          "value": "a",
          "optional": false,
          "typeAnnotation": null
        },
        "right": {
          "type": "Identifier",
          "span": {
            "start": 338,
            "end": 340,
            "ctxt": 0
          },
          "value": "b2",
          "optional": false
        }
      }
    },
    {
      "type": "ExpressionStatement",
      "span": {
        "start": 342,
        "end": 349,
        "ctxt": 0
      },
      "expression": {
        "type": "AssignmentExpression",
        "span": {
          "start": 342,
          "end": 348,
          "ctxt": 0
        },
        "operator": "=",
        "left": {
          "type": "Identifier",
          "span": {
            "start": 342,
            "end": 344,
            "ctxt": 0
          },
          "value": "b2",
          "optional": false,
          "typeAnnotation": null
        },
        "right": {
          "type": "Identifier",
          "span": {
            "start": 347,
            "end": 348,
            "ctxt": 0
          },
          "value": "a",
          "optional": false
        }
      }
    },
    {
      "type": "TsModuleDeclaration",
      "span": {
        "start": 360,
        "end": 841,
        "ctxt": 0
      },
      "declare": false,
      "global": false,
      "id": {
        "type": "Identifier",
        "span": {
          "start": 367,
          "end": 375,
          "ctxt": 0
        },
        "value": "Generics",
        "optional": false
      },
      "body": {
        "type": "TsModuleBlock",
        "span": {
          "start": 376,
          "end": 841,
          "ctxt": 0
        },
        "body": [
          {
            "type": "ClassDeclaration",
            "identifier": {
              "type": "Identifier",
              "span": {
                "start": 388,
                "end": 389,
                "ctxt": 0
              },
              "value": "A",
              "optional": false
            },
            "declare": false,
            "span": {
              "start": 382,
              "end": 437,
              "ctxt": 0
            },
            "decorators": [],
            "body": [
              {
                "type": "TsIndexSignature",
                "params": [
                  {
                    "type": "Identifier",
                    "span": {
                      "start": 417,
                      "end": 426,
                      "ctxt": 0
                    },
                    "value": "x",
                    "optional": false,
                    "typeAnnotation": {
                      "type": "TsTypeAnnotation",
                      "span": {
                        "start": 418,
                        "end": 426,
                        "ctxt": 0
                      },
                      "typeAnnotation": {
                        "type": "TsKeywordType",
                        "span": {
                          "start": 420,
                          "end": 426,
                          "ctxt": 0
                        },
                        "kind": "number"
                      }
                    }
                  }
                ],
                "typeAnnotation": {
                  "type": "TsTypeAnnotation",
                  "span": {
                    "start": 427,
                    "end": 430,
                    "ctxt": 0
                  },
                  "typeAnnotation": {
                    "type": "TsTypeReference",
                    "span": {
                      "start": 429,
                      "end": 430,
                      "ctxt": 0
                    },
                    "typeName": {
                      "type": "Identifier",
                      "span": {
                        "start": 429,
                        "end": 430,
                        "ctxt": 0
                      },
                      "value": "T",
                      "optional": false
                    },
                    "typeParams": null
                  }
                },
                "readonly": false,
                "static": false,
                "span": {
                  "start": 416,
                  "end": 431,
                  "ctxt": 0
                }
              }
            ],
            "superClass": null,
            "isAbstract": false,
            "typeParams": {
              "type": "TsTypeParameterDeclaration",
              "span": {
                "start": 389,
                "end": 405,
                "ctxt": 0
              },
              "parameters": [
                {
                  "type": "TsTypeParameter",
                  "span": {
                    "start": 390,
                    "end": 404,
                    "ctxt": 0
                  },
                  "name": {
                    "type": "Identifier",
                    "span": {
                      "start": 390,
                      "end": 391,
                      "ctxt": 0
                    },
                    "value": "T",
                    "optional": false
                  },
                  "in": false,
                  "out": false,
                  "const": false,
                  "constraint": {
                    "type": "TsTypeReference",
                    "span": {
                      "start": 400,
                      "end": 404,
                      "ctxt": 0
                    },
                    "typeName": {
                      "type": "Identifier",
                      "span": {
                        "start": 400,
                        "end": 404,
                        "ctxt": 0
                      },
                      "value": "Base",
                      "optional": false
                    },
                    "typeParams": null
                  },
                  "default": null
                }
              ]
            },
            "superTypeParams": null,
            "implements": []
          },
          {
            "type": "ClassDeclaration",
            "identifier": {
              "type": "Identifier",
              "span": {
                "start": 449,
                "end": 450,
                "ctxt": 0
              },
              "value": "B",
              "optional": false
            },
            "declare": false,
            "span": {
              "start": 443,
              "end": 510,
              "ctxt": 0
            },
            "decorators": [],
            "body": [
              {
                "type": "TsIndexSignature",
                "params": [
                  {
                    "type": "Identifier",
                    "span": {
                      "start": 478,
                      "end": 487,
                      "ctxt": 0
                    },
                    "value": "x",
                    "optional": false,
                    "typeAnnotation": {
                      "type": "TsTypeAnnotation",
                      "span": {
                        "start": 479,
                        "end": 487,
                        "ctxt": 0
                      },
                      "typeAnnotation": {
                        "type": "TsKeywordType",
                        "span": {
                          "start": 481,
                          "end": 487,
                          "ctxt": 0
                        },
                        "kind": "number"
                      }
                    }
                  }
                ],
                "typeAnnotation": {
                  "type": "TsTypeAnnotation",
                  "span": {
                    "start": 488,
                    "end": 497,
                    "ctxt": 0
                  },
                  "typeAnnotation": {
                    "type": "TsTypeReference",
                    "span": {
                      "start": 490,
                      "end": 497,
                      "ctxt": 0
                    },
                    "typeName": {
                      "type": "Identifier",
                      "span": {
                        "start": 490,
                        "end": 497,
                        "ctxt": 0
                      },
                      "value": "Derived",
                      "optional": false
                    },
                    "typeParams": null
                  }
                },
                "readonly": false,
                "static": false,
                "span": {
                  "start": 477,
                  "end": 498,
                  "ctxt": 0
                }
              }
            ],
            "superClass": {
              "type": "Identifier",
              "span": {
                "start": 459,
                "end": 460,
                "ctxt": 0
              },
              "value": "A",
              "optional": false
            },
            "isAbstract": false,
            "typeParams": null,
            "superTypeParams": {
              "type": "TsTypeParameterInstantiation",
              "span": {
                "start": 460,
                "end": 466,
                "ctxt": 0
              },
              "params": [
                {
                  "type": "TsTypeReference",
                  "span": {
                    "start": 461,
                    "end": 465,
                    "ctxt": 0
                  },
                  "typeName": {
                    "type": "Identifier",
                    "span": {
                      "start": 461,
                      "end": 465,
                      "ctxt": 0
                    },
                    "value": "Base",
                    "optional": false
                  },
                  "typeParams": null
                }
              ]
            },
            "implements": []
          },
          {
            "type": "FunctionDeclaration",
            "identifier": {
              "type": "Identifier",
              "span": {
                "start": 525,
                "end": 528,
                "ctxt": 0
              },
              "value": "foo",
              "optional": false
            },
            "declare": false,
            "params": [],
            "decorators": [],
            "span": {
              "start": 516,
              "end": 839,
              "ctxt": 0
            },
            "body": {
              "type": "BlockStatement",
              "span": {
                "start": 547,
                "end": 839,
                "ctxt": 0
              },
              "stmts": [
                {
                  "type": "VariableDeclaration",
                  "span": {
                    "start": 557,
                    "end": 569,
                    "ctxt": 0
                  },
                  "kind": "var",
                  "declare": false,
                  "declarations": [
                    {
                      "type": "VariableDeclarator",
                      "span": {
                        "start": 561,
                        "end": 568,
                        "ctxt": 0
                      },
                      "id": {
                        "type": "Identifier",
                        "span": {
                          "start": 561,
                          "end": 562,
                          "ctxt": 0
                        },
                        "value": "a",
                        "optional": false,
                        "typeAnnotation": {
                          "type": "TsTypeAnnotation",
                          "span": {
                            "start": 562,
                            "end": 568,
                            "ctxt": 0
                          },
                          "typeAnnotation": {
                            "type": "TsTypeReference",
                            "span": {
                              "start": 564,
                              "end": 568,
                              "ctxt": 0
                            },
                            "typeName": {
                              "type": "Identifier",
                              "span": {
                                "start": 564,
                                "end": 565,
                                "ctxt": 0
                              },
                              "value": "A",
                              "optional": false
                            },
                            "typeParams": {
                              "type": "TsTypeParameterInstantiation",
                              "span": {
                                "start": 565,
                                "end": 568,
                                "ctxt": 0
                              },
                              "params": [
                                {
                                  "type": "TsTypeReference",
                                  "span": {
                                    "start": 566,
                                    "end": 567,
                                    "ctxt": 0
                                  },
                                  "typeName": {
                                    "type": "Identifier",
                                    "span": {
                                      "start": 566,
                                      "end": 567,
                                      "ctxt": 0
                                    },
                                    "value": "T",
                                    "optional": false
                                  },
                                  "typeParams": null
                                }
                              ]
                            }
                          }
                        }
                      },
                      "init": null,
                      "definite": false
                    }
                  ]
                },
                {
                  "type": "VariableDeclaration",
                  "span": {
                    "start": 578,
                    "end": 610,
                    "ctxt": 0
                  },
                  "kind": "var",
                  "declare": false,
                  "declarations": [
                    {
                      "type": "VariableDeclarator",
                      "span": {
                        "start": 582,
                        "end": 610,
                        "ctxt": 0
                      },
                      "id": {
                        "type": "Identifier",
                        "span": {
                          "start": 582,
                          "end": 583,
                          "ctxt": 0
                        },
                        "value": "b",
                        "optional": false,
                        "typeAnnotation": {
                          "type": "TsTypeAnnotation",
                          "span": {
                            "start": 583,
                            "end": 610,
                            "ctxt": 0
                          },
                          "typeAnnotation": {
                            "type": "TsTypeLiteral",
                            "span": {
                              "start": 585,
                              "end": 610,
                              "ctxt": 0
                            },
                            "members": [
                              {
                                "type": "TsIndexSignature",
                                "params": [
                                  {
                                    "type": "Identifier",
                                    "span": {
                                      "start": 588,
                                      "end": 597,
                                      "ctxt": 0
                                    },
                                    "value": "x",
                                    "optional": false,
                                    "typeAnnotation": {
                                      "type": "TsTypeAnnotation",
                                      "span": {
                                        "start": 589,
                                        "end": 597,
                                        "ctxt": 0
                                      },
                                      "typeAnnotation": {
                                        "type": "TsKeywordType",
                                        "span": {
                                          "start": 591,
                                          "end": 597,
                                          "ctxt": 0
                                        },
                                        "kind": "number"
                                      }
                                    }
                                  }
                                ],
                                "typeAnnotation": {
                                  "type": "TsTypeAnnotation",
                                  "span": {
                                    "start": 598,
                                    "end": 607,
                                    "ctxt": 0
                                  },
                                  "typeAnnotation": {
                                    "type": "TsTypeReference",
                                    "span": {
                                      "start": 600,
                                      "end": 607,
                                      "ctxt": 0
                                    },
                                    "typeName": {
                                      "type": "Identifier",
                                      "span": {
                                        "start": 600,
                                        "end": 607,
                                        "ctxt": 0
                                      },
                                      "value": "Derived",
                                      "optional": false
                                    },
                                    "typeParams": null
                                  }
                                },
                                "readonly": false,
                                "static": false,
                                "span": {
                                  "start": 587,
                                  "end": 608,
                                  "ctxt": 0
                                }
                              }
                            ]
                          }
                        }
                      },
                      "init": null,
                      "definite": false
                    }
                  ]
                },
                {
                  "type": "ExpressionStatement",
                  "span": {
                    "start": 619,
                    "end": 625,
                    "ctxt": 0
                  },
                  "expression": {
                    "type": "AssignmentExpression",
                    "span": {
                      "start": 619,
                      "end": 624,
                      "ctxt": 0
                    },
                    "operator": "=",
                    "left": {
                      "type": "Identifier",
                      "span": {
                        "start": 619,
                        "end": 620,
                        "ctxt": 0
                      },
                      "value": "a",
                      "optional": false,
                      "typeAnnotation": null
                    },
                    "right": {
                      "type": "Identifier",
                      "span": {
                        "start": 623,
                        "end": 624,
                        "ctxt": 0
                      },
                      "value": "b",
                      "optional": false
                    }
                  }
                },
                {
                  "type": "ExpressionStatement",
                  "span": {
                    "start": 643,
                    "end": 649,
                    "ctxt": 0
                  },
                  "expression": {
                    "type": "AssignmentExpression",
                    "span": {
                      "start": 643,
                      "end": 648,
                      "ctxt": 0
                    },
                    "operator": "=",
                    "left": {
                      "type": "Identifier",
                      "span": {
                        "start": 643,
                        "end": 644,
                        "ctxt": 0
                      },
                      "value": "b",
                      "optional": false,
                      "typeAnnotation": null
                    },
                    "right": {
                      "type": "Identifier",
                      "span": {
                        "start": 647,
                        "end": 648,
                        "ctxt": 0
                      },
                      "value": "a",
                      "optional": false
                    }
                  }
                },
                {
                  "type": "VariableDeclaration",
                  "span": {
                    "start": 668,
                    "end": 702,
                    "ctxt": 0
                  },
                  "kind": "var",
                  "declare": false,
                  "declarations": [
                    {
                      "type": "VariableDeclarator",
                      "span": {
                        "start": 672,
                        "end": 702,
                        "ctxt": 0
                      },
                      "id": {
                        "type": "Identifier",
                        "span": {
                          "start": 672,
                          "end": 674,
                          "ctxt": 0
                        },
                        "value": "b2",
                        "optional": false,
                        "typeAnnotation": {
                          "type": "TsTypeAnnotation",
                          "span": {
                            "start": 674,
                            "end": 702,
                            "ctxt": 0
                          },
                          "typeAnnotation": {
                            "type": "TsTypeLiteral",
                            "span": {
                              "start": 676,
                              "end": 702,
                              "ctxt": 0
                            },
                            "members": [
                              {
                                "type": "TsIndexSignature",
                                "params": [
                                  {
                                    "type": "Identifier",
                                    "span": {
                                      "start": 679,
                                      "end": 688,
                                      "ctxt": 0
                                    },
                                    "value": "x",
                                    "optional": false,
                                    "typeAnnotation": {
                                      "type": "TsTypeAnnotation",
                                      "span": {
                                        "start": 680,
                                        "end": 688,
                                        "ctxt": 0
                                      },
                                      "typeAnnotation": {
                                        "type": "TsKeywordType",
                                        "span": {
                                          "start": 682,
                                          "end": 688,
                                          "ctxt": 0
                                        },
                                        "kind": "number"
                                      }
                                    }
                                  }
                                ],
                                "typeAnnotation": {
                                  "type": "TsTypeAnnotation",
                                  "span": {
                                    "start": 689,
                                    "end": 699,
                                    "ctxt": 0
                                  },
                                  "typeAnnotation": {
                                    "type": "TsTypeReference",
                                    "span": {
                                      "start": 691,
                                      "end": 699,
                                      "ctxt": 0
                                    },
                                    "typeName": {
                                      "type": "Identifier",
                                      "span": {
                                        "start": 691,
                                        "end": 699,
                                        "ctxt": 0
                                      },
                                      "value": "Derived2",
                                      "optional": false
                                    },
                                    "typeParams": null
                                  }
                                },
                                "readonly": false,
                                "static": false,
                                "span": {
                                  "start": 678,
                                  "end": 700,
                                  "ctxt": 0
                                }
                              }
                            ]
                          }
                        }
                      },
                      "init": null,
                      "definite": false
                    }
                  ]
                },
                {
                  "type": "ExpressionStatement",
                  "span": {
                    "start": 711,
                    "end": 718,
                    "ctxt": 0
                  },
                  "expression": {
                    "type": "AssignmentExpression",
                    "span": {
                      "start": 711,
                      "end": 717,
                      "ctxt": 0
                    },
                    "operator": "=",
                    "left": {
                      "type": "Identifier",
                      "span": {
                        "start": 711,
                        "end": 712,
                        "ctxt": 0
                      },
                      "value": "a",
                      "optional": false,
                      "typeAnnotation": null
                    },
                    "right": {
                      "type": "Identifier",
                      "span": {
                        "start": 715,
                        "end": 717,
                        "ctxt": 0
                      },
                      "value": "b2",
                      "optional": false
                    }
                  }
                },
                {
                  "type": "ExpressionStatement",
                  "span": {
                    "start": 736,
                    "end": 743,
                    "ctxt": 0
                  },
                  "expression": {
                    "type": "AssignmentExpression",
                    "span": {
                      "start": 736,
                      "end": 742,
                      "ctxt": 0
                    },
                    "operator": "=",
                    "left": {
                      "type": "Identifier",
                      "span": {
                        "start": 736,
                        "end": 738,
                        "ctxt": 0
                      },
                      "value": "b2",
                      "optional": false,
                      "typeAnnotation": null
                    },
                    "right": {
                      "type": "Identifier",
                      "span": {
                        "start": 741,
                        "end": 742,
                        "ctxt": 0
                      },
                      "value": "a",
                      "optional": false
                    }
                  }
                },
                {
                  "type": "VariableDeclaration",
                  "span": {
                    "start": 762,
                    "end": 789,
                    "ctxt": 0
                  },
                  "kind": "var",
                  "declare": false,
                  "declarations": [
                    {
                      "type": "VariableDeclarator",
                      "span": {
                        "start": 766,
                        "end": 789,
                        "ctxt": 0
                      },
                      "id": {
                        "type": "Identifier",
                        "span": {
                          "start": 766,
                          "end": 768,
                          "ctxt": 0
                        },
                        "value": "b3",
                        "optional": false,
                        "typeAnnotation": {
                          "type": "TsTypeAnnotation",
                          "span": {
                            "start": 768,
                            "end": 789,
                            "ctxt": 0
                          },
                          "typeAnnotation": {
                            "type": "TsTypeLiteral",
                            "span": {
                              "start": 770,
                              "end": 789,
                              "ctxt": 0
                            },
                            "members": [
                              {
                                "type": "TsIndexSignature",
                                "params": [
                                  {
                                    "type": "Identifier",
                                    "span": {
                                      "start": 773,
                                      "end": 782,
                                      "ctxt": 0
                                    },
                                    "value": "x",
                                    "optional": false,
                                    "typeAnnotation": {
                                      "type": "TsTypeAnnotation",
                                      "span": {
                                        "start": 774,
                                        "end": 782,
                                        "ctxt": 0
                                      },
                                      "typeAnnotation": {
                                        "type": "TsKeywordType",
                                        "span": {
                                          "start": 776,
                                          "end": 782,
                                          "ctxt": 0
                                        },
                                        "kind": "number"
                                      }
                                    }
                                  }
                                ],
                                "typeAnnotation": {
                                  "type": "TsTypeAnnotation",
                                  "span": {
                                    "start": 783,
                                    "end": 786,
                                    "ctxt": 0
                                  },
                                  "typeAnnotation": {
                                    "type": "TsTypeReference",
                                    "span": {
                                      "start": 785,
                                      "end": 786,
                                      "ctxt": 0
                                    },
                                    "typeName": {
                                      "type": "Identifier",
                                      "span": {
                                        "start": 785,
                                        "end": 786,
                                        "ctxt": 0
                                      },
                                      "value": "T",
                                      "optional": false
                                    },
                                    "typeParams": null
                                  }
                                },
                                "readonly": false,
                                "static": false,
                                "span": {
                                  "start": 772,
                                  "end": 787,
                                  "ctxt": 0
                                }
                              }
                            ]
                          }
                        }
                      },
                      "init": null,
                      "definite": false
                    }
                  ]
                },
                {
                  "type": "ExpressionStatement",
                  "span": {
                    "start": 798,
                    "end": 805,
                    "ctxt": 0
                  },
                  "expression": {
                    "type": "AssignmentExpression",
                    "span": {
                      "start": 798,
                      "end": 804,
                      "ctxt": 0
                    },
                    "operator": "=",
                    "left": {
                      "type": "Identifier",
                      "span": {
                        "start": 798,
                        "end": 799,
                        "ctxt": 0
                      },
                      "value": "a",
                      "optional": false,
                      "typeAnnotation": null
                    },
                    "right": {
                      "type": "Identifier",
                      "span": {
                        "start": 802,
                        "end": 804,
                        "ctxt": 0
                      },
                      "value": "b3",
                      "optional": false
                    }
                  }
                },
                {
                  "type": "ExpressionStatement",
                  "span": {
                    "start": 820,
                    "end": 827,
                    "ctxt": 0
                  },
                  "expression": {
                    "type": "AssignmentExpression",
                    "span": {
                      "start": 820,
                      "end": 826,
                      "ctxt": 0
                    },
                    "operator": "=",
                    "left": {
                      "type": "Identifier",
                      "span": {
                        "start": 820,
                        "end": 822,
                        "ctxt": 0
                      },
                      "value": "b3",
                      "optional": false,
                      "typeAnnotation": null
                    },
                    "right": {
                      "type": "Identifier",
                      "span": {
                        "start": 825,
                        "end": 826,
                        "ctxt": 0
                      },
                      "value": "a",
                      "optional": false
                    }
                  }
                }
              ]
            },
            "generator": false,
            "async": false,
            "typeParameters": {
              "type": "TsTypeParameterDeclaration",
              "span": {
                "start": 528,
                "end": 544,
                "ctxt": 0
              },
              "parameters": [
                {
                  "type": "TsTypeParameter",
                  "span": {
                    "start": 529,
                    "end": 543,
                    "ctxt": 0
                  },
                  "name": {
                    "type": "Identifier",
                    "span": {
                      "start": 529,
                      "end": 530,
                      "ctxt": 0
                    },
                    "value": "T",
                    "optional": false
                  },
                  "in": false,
                  "out": false,
                  "const": false,
                  "constraint": {
                    "type": "TsTypeReference",
                    "span": {
                      "start": 539,
                      "end": 543,
                      "ctxt": 0
                    },
                    "typeName": {
                      "type": "Identifier",
                      "span": {
                        "start": 539,
                        "end": 543,
                        "ctxt": 0
                      },
                      "value": "Base",
                      "optional": false
                    },
                    "typeParams": null
                  },
                  "default": null
                }
              ]
            },
            "returnType": null
          }
        ]
      }
    }
  ],
  "interpreter": null
}