const parse = require('json-to-ast');
const settings = {
  // Appends location information. Default is <true>
  loc: true,
  // Appends source information to node’s location. Default is <null>
  source: 'data.json'
};
parse('{"a": 1}', settings);

{
  type: 'Object',
  children: [
    {
      type: 'Property',
      key: {
        type: 'Identifier',
        value: 'a',
        raw: '"a"',
        loc: {
          start: { line: 1, column: 2, offset: 1 },
          end: { line: 1, column: 5, offset: 4 },
          source: 'data.json'
        }
      },
      value: {
        type: 'Literal',
        value: 1,
        raw: '1',
        loc: {
          start: { line: 1, column: 7, offset: 6 },
          end: { line: 1, column: 8, offset: 7 },
          source: 'data.json'
        }
      },
      loc: {
        start: { line: 1, column: 2, offset: 1 },
        end: { line: 1, column: 8, offset: 7 },
        source: 'data.json'
      }
    }
  ],
  loc: {
    start: { line: 1, column: 1, offset: 0 },
    end: { line: 1, column: 9, offset: 8 },
    source: 'data.json'
  }
}

{
  type: 'Object',
  children: <Property>[],
  loc?: Object
}

{
  type: 'Property',
  key: <Identifier>,
  value: Object | Array | <Literal>,
  loc?: Object
}

{
  type: 'Identifier',
  value: string,
  raw: string,
  loc?: Object
}

{
  type: 'Array',
  children: (Object | Array | <Literal>)[],
  loc?: Object
}

{
  type: 'Literal',
  value: string | number | boolean | null,
  raw: string,
  loc?: Object
}