How to use the @delon/util.InputBoolean function in @delon/util

_error: string;

  // #region fields

  @Input() optional: string | TemplateRef;
  @Input() optionalHelp: string | TemplateRef;
  @Input()
  set error(val: string | { [key: string]: string }) {
    this.errorData = typeof val === 'string' ? { '': val } : val;
  }
  @Input() extra: string;
  @Input() label: string | TemplateRef;
  @Input() @InputNumber(null) col: number;
  @Input() @InputBoolean() required = false;
  @Input() controlClass: string = '';
  @Input() @InputBoolean(null) line: boolean;
  @Input() @InputNumber(null) labelWidth: number;

  @Input()
  set id(value: string) {
    this._id = value;
    this._autoId = false;
  }

  _id = `_se-${nextUniqueId++}`;
  _autoId = true;

  // #endregion

  get paddingValue(): number {
    return this.parent.gutter / 2;
  }

encapsulation: ViewEncapsulation.None,
})
export class SVComponent implements AfterViewInit, OnChanges {
  @ViewChild('conEl', { static: false })
  private conEl: ElementRef;
  private el: HTMLElement;
  private clsMap: string[] = [];

  // #region fields

  @Input() optional: string | TemplateRef;
  @Input() optionalHelp: string | TemplateRef;
  @Input() label: string | TemplateRef;
  @Input() unit: string | TemplateRef;
  @Input() @InputNumber(null) col: number;
  @Input() @InputBoolean(null) default: boolean;
  @Input() type: 'primary' | 'success' | 'danger' | 'warning';

  // #endregion

  get paddingValue(): number {
    return this.parent && this.parent.gutter / 2;
  }

  get labelWidth(): number | null {
    const { labelWidth, layout } = this.parent;
    return layout === 'horizontal' ? labelWidth : null;
  }

  constructor(
    el: ElementRef,
    @Host() @Optional() public parent: SVContainerComponent,