History of main 10 changes

In src/main.rs, lines 12–29 on fe9586d93fb14837bcb44b78acbb490d9dc3ffdde51767e8cab215020bc432a5. Every change that wrote or deleted one of these lines, or deleted a line from between them. Exact, because each line keeps its identity across edits; edits elsewhere in the file are not here. Also: oxy log -L 12,29:src/main.rs.