How a Span Fits in Eight Bytes: rustc's Four-Format Packed Encoding
rustc’s Span is 64 bits with four internal layouts selected by a sentinel prefix, decoded by a macro-generated if-chain because the enum version did not optimise.
rustc’s Span is 64 bits with four internal layouts selected by a sentinel prefix, decoded by a macro-generated if-chain because the enum version did not optimise.