var classof = require('./classof-raw');
var regexpExec = require('./regexp-exec');

// `RegExpExec` abstract operation
// https://tc39.github.io/ecma262/#sec-regexpexec
module.exports = function (R, S) {
  var exec = R.exec;
  if (typeof exec === 'function') {
    var result = exec.call(R, S);
    if (typeof result !== 'object') {
      throw TypeError('RegExp exec method returned something other than an Object or null');
    }
    return result;
  }

  if (classof(R) !== 'RegExp') {
    throw TypeError('RegExp#exec called on incompatible receiver');
  }

  return regexpExec.call(R, S);
};