Proc macro - bracket token - input.parse::<Token![(]>()

help
1

Hi folks,

I can't figure out how to write this: input.parse::<Token![(]>() (for a proc macro).

I tried different escapes to escape the bracket....

2

Are you looking for token::Paren?

3

In Rust, ( and ) are never tokens by themselves — they are always kept together with their contents as a single token tree. So it’s not just that Token![(] can’t be written — a lone left parenthesis never exists, either.

I haven’t personally written any custom parsers with syn, but this looks promising: https://docs.rs/syn/2/syn/macro.parenthesized.html

Parse a set of parentheses and expose their content to subsequent parsers.

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