escape parentheses in stepdefs?

[nruth]

Given a scenario line like

Then I'm warned (with emphasis) that they are x

or as in the examples at https://cucumber.io/docs/gherkin/reference/

Then he (or she) will live forever ;-)

It seems like this can't be matched by a turnip stepdef because parens are used for optional words. Is there an escape mechanism, like in regular expressions? OPTIONAL_WORD_REGEXP looks like there isn't?

I imagine the same thing could apply to : and / for placeholders and alternate words.