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std.compress.inflate implements rfc 1951 in about 250 lines of pith: an lsb-first bit reader, canonical huffman decoding by the first-code walk (a few comparisons per symbol, no decode tables to build), the dynamic-tree run-length machinery, and lz77 back-reference copies from the output window. gzip.decompress routes every block type through it — stored, fixed huffman, dynamic huffman — and verifies the crc32 and length trailer, so files produced by other tools now read correctly. verified against system gzip at levels 1, 6, and 9: a 200KB source file decompresses byte-identical, and random binary round-trips. a committed gzip -9 fixture pins interop in the test suite, and logscan's golden check now hands the tool a real system-gzip file on every ci run instead of a pith-written one. the honest remainder is documented in limitations: compress() still writes stored blocks, so pith-written archives are larger than their input. the compressor is the other half of the project.
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summary
std.compress.inflate: rfc 1951 in ~250 lines of pith — lsb-first bit reader, canonical huffman decoding via the first-code walk (no decode tables), dynamic-tree run-length machinery, lz77 back-reference copies.gzip.decompressroutes all three block types through it with crc32 + length trailer verification — files from other tools now read correctly, closing the documented interop gap.verification
gzip -9fixture pins interop in the suitehonest remainder
compress()still writes stored blocks (pith-written archives exceed their input) — documented in limitations; the compressor is the other half of the project.what was tested
full suite green (all four golden checks, logscan now on real gzip), fixed point byte-identical, seed refreshed, fmt + doc gates clean.