Regexp parentheses string parsing issue

I have a string that looks like:

'Hello (string_here.d) (string)'

I've messed with regexp for the last hour trying to get the 'string_here.d' from within the parentheses with no avail. I thought '([.]+)' or '\([.]+\)' would work, but them I thought it was the '.' causing me trouble so I tried '([.]+\.d)' and '\([.]+\.d\)'. I tried about 100 different variations of the above. What pattern would get me the string in the parentheses that has the . character in it.

Answer 1

[per isakson]

Not the most robust expression, but it works in this case

    str = 'Hello (string_here.d) (string)';
    cac = regexp( str, '(?<=\()\S+(?=\))', 'match', 'once' )

returns

    cac =
    string_here.d