['<code>/(?^)/</code>', 'construct to reset to default modifiers'],
['<code>/(?{ m() })/</code>', 'regular expressions can be nested in <code>/(?{})/</code> and <code>/(??{})/</code>', v5.20],
[q"<code>use re '/flags'</code>", 'customise default modifiers'],
['<code>/(?^)/</code>', 'construct to reset to default modifiers'],
['<code>/(?{ m() })/</code>', 'regular expressions can be nested in <code>/(?{})/</code> and <code>/(??{})/</code>', v5.20],
[q"<code>use re '/flags'</code>", 'customise default modifiers'],