strsplit by parentheses [duplicate]

Answer 1

Try this also:

 k<-"A B C (123-456-789)"
     regmatches(k,gregexpr("*.(\\d+).*",k))[[1]]
[1] "(123-456-789)"

With suggestion from @Arun:

regmatches(k, gregexpr('(?<=\\()[^A-Z ]+(?=\\))', k, perl=TRUE))[[1]]

With suggestion from @akrun:

regmatches(k, gregexpr('[0-9-]+', k))[[1]]