There was a similar request from another community member here Forms-heavy application with auto-save
And there is this plugin to help achieve that https://github.com/bigopon/aurelia-deep-computed
For your case, it would look like this
import { deepComputedFrom } from 'aurelia-deep-comnputed';
@inject(BindingEngine)
export MyExcelEl {
@bindable data;
constructor(be) {
this.bindingEngine = be;
}
bind() {
this.bindingEngine.propertyObserver(this, 'excelData').subsribe(newData => {
this.jexcel_instance.update(newData);
});
}
@deepComputedFrom('data')
get exelData() {
return this.data.map(() => {})
}
}