syntax_data: {"ast_node_type":"variable","tokens":[{"end":40,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let len = (span.hi - span.lo).0;
context_before:         let col_line = col_lo_trunc | line_lo_trunc | col_hi_trunc | line_hi_trunc;
context_after:         Hash::hash(&col_line, hasher);