syntax_data: {"ast_node_type":"other","tokens":[{"end":77,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // the index changing later: Nothing will ever change this temporary.
context_before:         // Making this a *fresh* temporary means we do not have to worry about
context_after:         // The "retagging" transformation (for Stacked Borrows) relies on this.