Make it easier to syntactically wrap another combinator.

[robrix]

For example parenthesized expressions. The parens are syntactically important but don’t contribute to the tree; the wrapped combinator’s result should therefore be passed through, and the wrapping terms should be dropped.

[robrix]

Equivalent to ignore(opening) ++ body ++ ignore(closing) I suppose.

[neilpa]

I didn't realize this equivalence and wrote a custom bookend operator. Although it was slightly different since it assumed body* which it then flattened the elements for.

[robrix]

bookend is a nice name for this!

[neilpa]

I probably spent far too much time thinking about it after iterating through wrap, quote, etc.

[bencochran]

Is this still necessary given #91? (namely opening *> body <* closing being now possible)

[robrix]

Probably not; closing.