syntax_data: {"ast_node_type":"import","tokens":[{"end":80,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:     // cfg=output.txt --print link-args=output.txt`, because outputs are printed
context_before:     // We disallow reusing the same path in multiple prints, such as `--print
context_after:     // by disparate pieces of the compiler, and keeping track of which files