module.exports = grammar({
  name: 'Dust',

  rules: {
    source_file: $ => repeat(choice($.comment, $.expression)),

    identifier: $ => /[a-zA-Z|_|.]+(_[a-zA-Z]+)*/,

    comment: $ => /(#)(.+?)([\n\r])/,

    expression: $ => choice(
      $.identifier,
      seq($.identifier, $.operator, $.identifier)
      
    ),

    operator: $ => choice(
      '=',
      '-',
      '+',
      ';',
      '/',
      '|',
      '&'
    ),

    integer: $ => /\d/,
  }
});