How to use the lit-html/directives/if-defined.ifDefined function in lit-html

readonly?: boolean;
  required?: boolean;
  validityMessage?: string;
  value?: string;
} = {}) => {
  const inner = !hasContent
    ? (undefined! as TemplateResult)
    : html`
        
      `;
  return !hasContent || !hasForm
    ? inner
    : html`
        <form>${inner}</form>
      `;
};

hasForm?: boolean;
  disabled?: boolean;
  labelText?: string;
  max?: number;
  min?: number;
  name?: string;
  step?: number;
  value?: number;
} = {}) => {
  const inner = !hasContent
    ? (undefined! as TemplateResult)
    : html`
        
      `;
  return !hasContent || !hasForm
    ? inner
    : html`
        <form>${inner}</form>
      `;
};

checkedText?: string;
  disabled?: boolean;
  id?: string;
  labelText?: string;
  name?: string;
  value?: string;
  uncheckedText?: string;
} = {}) => {
  const inner = !hasContent
    ? (undefined! as TemplateResult)
    : html`
        
      `;
  return !hasContent || !hasForm
    ? inner
    : html`
        <form>${inner}</form>
      `;
};

type?: string;
} = {}) =>
  !hasContent
    ? (undefined! as TemplateResult)
    : html`
        
      `;

disabled?: boolean;
  id?: string;
  labelText?: string;
  name?: string;
  value?: string;
  uncheckedText?: string;
} = {}) => {
  const inner = !hasContent
    ? (undefined! as TemplateResult)
    : html`
        
      `;
  return !hasContent || !hasForm
    ? inner
    : html`
        <form>${inner}</form>
      `;
};

export default value => ifDefined(value ?? undefined);

render() {
        return html`
            <form action="${ifDefined(this.action)}" name="${ifDefined(this.name)}">
                
            </form>
        `;
    }

({ id: columnId, sortCycle, title }) => {
                const sortDirectionForThisCell =
                  sortCycle && (columnId === sortColumnId ? sortDirection : TABLE_SORT_DIRECTION.NONE);
                return html`
                  
                    ${title}
                  
                `;
              }
            )}

private async loadFeatureApp(): Promise {
      try {
        if (!this.src) {
          throw new Error('No src provided.');
        }

        const definition = await featureAppManager.getAsyncFeatureAppDefinition(
          prependBaseUrl(this.baseUrl, this.src)
        ).promise;

        return html`
          
            
          
        `;
      } catch (error) {
        logger.error(error);

        return html`
          
        `;
      }
    }
  }

const myApp = (text: string, disabled: boolean) => html`
	<img src="${ifDefined(src)}">

	<style>
		my-button {
			color: ${"green"};
		}

		a {
			color: rebeccapurple;
			additive-symbols: cross-fade();
		}
	</style>

	

	<a download="hello"></a>