[SalesForce] Regex on lightning:datatable

I'm using lightning:datatable to display the Account object in a table. I've also added a regex that lets users search for any field in any column. What I wish to do is, if there are no matches, display a button to let the user create a new account.

Basically, I got this table with a search functionality here:

<lightning:input type="text"
                 onchange="{!c.filter}"
                 value="{!v.filter}"
                 placeholder="Search any column" />

<lightning:datatable aura:id="lightningTable"
                     data="{! v.accounts }"
                     columns="{! v.mycolumns }"
                     keyField="Id"
                     onrowaction="{! c.handleRowAction }"
                     onsort="{!c.updateColumnSorting}"
                     sortedBy="{!v.sortedBy}"
                     sortedDirection="{!v.sortedDirection}"
                     hideCheckboxColumn="true"/>

That triggers this controller everytime a user types in the search field:

filter: function (component, event, helper) {
    var data = component.get("v.backingdata"),
        term = component.get("v.filter"),
        results = data, regex;
    try {
        regex = new RegExp(term, "i");
        // filter checks each row, constructs new array where function returns true
        results = data.filter(row => regex.test(row.Name) ||
        regex.test(row.BillingStreet) ||
        regex.test(row.BillingPostalCode) ||
        regex.test(row.BillingCity) ||
        regex.test(row.BillingCountry));
    }
    catch (e) {
        // invalid regex, use full list
        console.log(e);
    }
    if (results.length === 0) {
        // Show a lightning button to let the user add a new account
    }
    component.set("v.accounts", results);
},

What I wish to do is, if there are no results from the search, I'd like to display a lightning button, but not sure how to put that, seeing as it's a lightning:datatable.

Any ideas?