{"ast_node_type":"variable","tokens":[{"end":46,"kind":"keyword","start":0,"text":"let"}]}
    let macro_call = macro_expr.macro_call()?;
fn compute_dbg_replacement(macro_expr: ast::MacroExpr) -> Option<(TextRange, Option<ast::Expr>)> {
    let tt = macro_call.token_tree()?;