syntax_data: {"ast_node_type":"other","tokens":[{"end":61,"kind":"keyword","start":0,"text":"flatten_format_args:"}]}
source_snippet:     flatten_format_args: bool = (true, parse_bool, [TRACKED],
context_before:         "make the x18 register reserved on AArch64 (default: no)"),
context_after:         "flatten nested format_args!() and literals into a simplified format_args!() call \