Method restore_depth

crates/kernel/src/tc.rs:519–523

Restore context to a previously saved depth.

(&mut self, saved: usize)

      return false;
    }
    let level = n - 1 - idx_us;
    self.let_vals[level].is_some()
  }

  /// Save current depth for later restore.
  pub fn save_depth(&self) -> usize {
    self.ctx.len()
  }