TryGhost/Ghost

<button
    class="tab {{if this.isSelectedTab "tab-selected" }}"
    id="{{this.id}}"
    type="button"
    role="tab"
    aria-selected="{{this.isSelectedTab}}"
    aria-controls="{{this.id}}-panel"
    tabindex="{{if this.isSelectedTab "0" "-1"}}"
    {{on "click" this.handleClick}}
    {{on "keyup" this.handleKeyup}}
>
    {{yield}}
</button>