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    Import std.compress.xz

    std.compress.xz

    The .xz compression format.

    The .xz format, over liblzma: LZMA2, in streams with a CRC64 check. Its Compress and Decompress work at once, and its Compressor and Decompressor take bytes in turn and give what came out of them so far, for data that comes in parts. Levels are xz's presets, from 0, the fastest, to 9, the smallest, and are 6 by default, as xz's; the higher ones take much more memory, up to 674 MiB to compress at 9, and 65 MiB to decompress. A Decompress reads streams one after another, and the padding between them, as xz does.

    Examples

    // Each format's Compressor and Decompressor take bytes in turn.
Local compressor = XZCompressor(6)
Local packed = compressor.Add("a part, and ".Bytes)
packed.AddAll(compressor.Add("the rest".Bytes))
packed.AddAll(compressor.Finish())
Local decompressor = XZDecompressor()
Local text = Try decompressor.Add(packed)
text.AddAll(Try decompressor.Finish())
Expect(String.FromUtf8(text) == "a part, and the rest")

    std/compress/xz.fb

    Types

    XZ struct 

    Public Struct XZ

    The .xz format's streams.

    Examples

    Local data = "small, smaller, smallest, small, smaller, smallest".Repeated(100).Bytes
Local packed = XZ.Compress(data)
Expect(packed.Count < data.Count)
Local unpacked = Try XZ.Decompress(packed)
Expect(unpacked == data)

    std/compress/xz.fb, line 53

    • @PanicsAtCaller Public Static Method Compress(data: UInt8[], level: Int = 6): UInt8[] static method #

      The data, compressed at the level. Panics when the level isn't from 0 to 9.

    • @PanicsAtCaller Public Static Method Decompress(data: UInt8[], limit: Int = MOST_BYTES): UInt8[] Throws IOError static method #

      The bytes the data is compressed from, each stream's after the last's, or an IOError when it isn't XZ's, ends early, or would come to more than limit bytes. Panics when the limit is negative.

    XZCompressor class 

    Public Class XZCompressor Implements Coder

    XZ's bytes made in turn: Add gives what compressing the bytes it takes has made so far, and Finish what's left, which ends a stream, and starts again.

    std/compress/xz.fb, line 83

    • @PanicsAtCaller Public New(level: Int = 6) constructor #

      A new XZCompressor at the level. Panics when it isn't from 0 to 9.

    • Public Method Add(data: UInt8[]): UInt8[] method #

      Compresses data, and gives the XZ bytes it has made so far, which can be none, as it holds some back to compress with what comes next.

    • Public Method Finish(): UInt8[] method #

      The rest of the bytes, which end the stream, and starts again, for another.

    XZDecompressor class 

    Public Class XZDecompressor Implements Coder

    XZ's bytes taken in turn, a stream after another: Add gives what the bytes it takes decompress to so far, and Finish what's left once they've all been added, and starts again. Each throws an IOError when the bytes aren't XZ's or would come to more than the limit, and Finish when they end early.

    std/compress/xz.fb, line 116

    • @PanicsAtCaller Public New(limit: Int = MOST_BYTES) constructor #

      A new XZDecompressor that gives at most limit bytes. Panics when the limit is negative.

    • Public Method Add(data: UInt8[]): UInt8[] Throws IOError method #

      Decompresses data, and gives the bytes it comes to so far. Throws an IOError when the bytes aren't XZ's, or would come to more than the limit.

    • Public Method Finish(): UInt8[] Throws IOError method #

      The rest of the bytes, once every one is added, and starts again. Throws an IOError when the stream ended early.

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