syntax_data: {"ast_node_type":"variable","tokens":[{"end":50,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:     let cmdline = Path::new("/proc/self/cmdline");
context_before:     // stat always says that /proc/self/cmdline is length 0, but it isn't.
context_after:     let len = std::fs::metadata(cmdline).unwrap().len() as usize;