syntax_data: {"ast_node_type":"other","tokens":[{"end":43,"kind":"keyword","start":0,"text":"for"}]}
source_snippet:                 for arm_id in arms.iter() {
context_before:                 print_indented!(self, "arms: [", depth_lvl + 1);
context_after:                     self.print_arm(*arm_id, depth_lvl + 2);