s <- 'Lorem ipsum dolor sit amet, consectetur adipisicing elit.'
if (stri_install_check(silent=TRUE))
stri_locate_last('XaaaaX',
regex=c('\\p{Ll}', '\\p{Ll}+', '\\p{Ll}{2,3}', '\\p{Ll}{2,3}?'))
if (stri_install_check(silent=TRUE))
stri_locate_last('Bartolini', fixed=letters[1:3])
if (stri_install_check(silent=TRUE))
stri_locate_last('a b c', charclass='\\p{Zs}')
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