{"ast_node_type":"function","tokens":[{"end":94,"kind":"keyword","start":0,"text":"pub"}]}
    pub fn at_token(sema: &Semantics<'db, RootDatabase>, token: SyntaxToken) -> Option<Self> {
    /// Returns information about the call argument this token is part of.
        let (signature, active_parameter) = callable_for_token(sema, token)?;