Does the example compile?

CC @HowardHinnant

The example as corrected compiles. The uncorrected code does not.

nitpick: I use {} for construction when possible to disambiguate it visually from a function call which uses ().

I do want to point out that the standard library specifications try to avoid brace-initialization, due to bad experiences with narrowing prohibitions getting into the way. That doesn't necessarily affect examples, though.

@jwakely , any opinion for this particular case?

I was mostly noting that a existing examples in this area also use braces, so I wasn't concerned by making this locally consistent. That does not constitute endoresement of a wider policy, and I'd be happy to discuss this in a wider context.