It's unused.
Just in case, add a unit test case for using the fmt library to
format it (that includes fmt::to_string(std::initializer_list)).
Note that the existing to_string implementation
used square brackets to enclose the initializer_list
but the new, standardized form uses curly braces.
This doesn't break anything since to_string(initializer_list)
wasn't used.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
As seen in https://github.com/scylladb/scylladb/issues/13146
the current implementation is not general enough
to provide print helpers for all kind of containers.
Modernize the implementation using templates based
on std::ranges::range and using fmt::join.
Extend unit test for formatting different types of ranges,
boost::transformed ranges, deque.
Fixes#13146
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
this is a part of a series to migrating from `operator<<(ostream&, ..)`
based formatting to fmtlib based formatting. the goal here is to enable
fmtlib to print `optional<T>` without the help of `operator<<()`.
this change also enables us to ditch more `operator<<()`s in future.
as we are relying on `operator<<(ostream&, const optional<T>&)` for
printing instances of `optional<T>`, and `operator<<(ostream&, const optional<T>&)`
in turn uses the `operator<<(ostream&, const T&)`. so, the new
specialization of `fmt::formatter<optional<>>` will remove yet
another caller of these operators.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
`join` can easily be confused with boost::algorithm::join
so make it more visible that we're using scylla's
utils implementation.
Also, move `struct print_with_comma` to utils::internal.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
