The body of an expansion statement is treated as if it's part of a template
(e.g. you have to put `typename` in various places). If a structured
binding pack could appear outside a template, it would force the entire
remainder of the current scope to be treated as a template.

On Wed, Feb 4, 2026 at 8:05 AM Артём Колпаков via Std-Discussion <
std-discussion_at_[hidden]> wrote:

> Good afternoon. Why can't the structured binding pack be used outside of
> the template, whereas the expansion statement can. It seems to me that for
> tuple-like types there is no significant difference between these language
> features, but to use the first one, you have to use a synthetic template
> where there is no real one. Is this a language defect?
>
> I'm not sure what the documents say about this. I am writing immediately
> after observing the error on goldbolt.
>
> Thank you for your attention.
> Artyom Kolpakov
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-- 
*Brian Bi*