{"ast_node_type":"variable","tokens":[{"end":55,"kind":"keyword","start":0,"text":"let"}]}
    let param: ast::Param = ctx.find_node_at_offset()?;
pub(crate) fn remove_unused_param(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()> {
    let ident_pat = match param.pat()? {