syntax_data: {"ast_node_type":"other","tokens":[{"end":42,"kind":"keyword","start":0,"text":"nightly_options_on_stable,"}]}
source_snippet:                 nightly_options_on_stable,
context_before:                 "{} nightly option{} were parsed",
context_after:                 if nightly_options_on_stable > 1 { "s" } else { "" }