syntax_data: {"ast_node_type":"other","tokens":[{"end":78,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // with remaining match pairs, to avoid exponential blowup if possible
context_before:         // It's important to perform the above simplifications _before_ dealing
context_after:         // (for trivial or-patterns), and avoid useless work (for never patterns).