Method _createControl

packages/forms/src/form_builder.ts:422–442

@internal

(
    controls: T | FormControlState<T> | ControlConfig<T> | FormControl<T> | AbstractControl<T>,
  )

  /** @internal */
  _createControl<T>(
    controls: T | FormControlState<T> | ControlConfig<T> | FormControl<T> | AbstractControl<T>,
  ): FormControl<T> | FormControl<T | null> | AbstractControl<T> {
    if (controls instanceof FormControl) {
      return controls as FormControl<T>;
    } else if (controls instanceof AbstractControl) {
      // A control; just return it
      return controls;
    } else if (Array.isArray(controls)) {
      // ControlConfig Tuple
      const value: T | FormControlState<T> = controls[0];
      const validator: ValidatorFn | ValidatorFn[] | null =
        controls.length > 1 ? controls[1]! : null;
      const asyncValidator: AsyncValidatorFn | AsyncValidatorFn[] | null =
        controls.length > 2 ? controls[2]! : null;
      return this.control<T>(value, validator, asyncValidator);
    } else {
      // T or FormControlState<T>
      return this.control<T>(controls);
    }
  }
}

/**