gzip, zlib, flate, and bzip2

The gzip, zlib, and flate modules adapt Go's corresponding compress packages to whole Goblin values.

All three modules expose compress(data, level=DEFAULT_COMPRESSION, dest=unit) and decompress(data). Input may be Bytes or Str; output is always Bytes. Malformed compressed input raises ParseError.

Compression-level constants mirror compress/flate: NO_COMPRESSION, BEST_SPEED, BEST_COMPRESSION, DEFAULT_COMPRESSION, and HUFFMAN_ONLY.

By default compress returns the compressed Bytes. Passing dest= streams the compressed output into any writer object — an object with a write(data) method, such as an open fs file — and the function returns unit:

import "x/compress/gzip"
import "fs"

var report = "line 1\nline 2\n"
var file = fs.create("report.txt.gz")
gzip.compress(report, dest=file)
file.close()

The bzip2 module exposes only decompress(data), returning Bytes. This mirrors Go's compress/bzip2, which provides a reader but no compressor.

import "x/compress/gzip"
import "x/compress/zlib"

var source = "Goblin Goblin Goblin"
var gz = gzip.compress(source, level=gzip.BEST_SPEED)
print(gzip.decompress(gz).decode())

var zl = zlib.compress(Bytes(source))
print(zlib.decompress(zl).decode())

The format used for decompression must match the format used for compression; gzip, zlib, and raw flate data are not interchangeable. An unsupported level raises ValueError, while corrupt or truncated compressed input raises ParseError. These APIs buffer the complete input (and, without dest=, the complete output), so they are best suited to bounded values rather than very large files or network streams.