bpo-32969: Expose some missing constants in zlib and fix the doc (GH-… · python/cpython@c4d77a6 (original) (raw)

`@@ -51,33 +51,35 @@ The available exception and functions in this module are:

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` Compresses the bytes in data, returning a bytes object containing compressed data.

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``` *level* is an integer from 0 to 9 or -1 controlling the level of compression;


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``

``` -

``1`` is fastest and produces the least compression, ``9`` is slowest and

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 produces the most. ``0`` is no compression. The default value is ``-1``

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(Z_DEFAULT_COMPRESSION). Z_DEFAULT_COMPRESSION represents a default

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 ``1`` (Z_BEST_SPEED) is fastest and produces the least compression, ``9`` (Z_BEST_COMPRESSION)

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is slowest and produces the most. ``0`` (Z_NO_COMPRESSION) is no compression.

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The default value is ``-1`` (Z_DEFAULT_COMPRESSION). Z_DEFAULT_COMPRESSION represents a default

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` compromise between speed and compression (currently equivalent to level 6).

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`` Raises the :exc:error exception if any error occurs.

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` .. versionchanged:: 3.6

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` level can now be used as a keyword parameter.

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.. function:: compressobj(level=-1, method=DEFLATED, wbits=15, memLevel=8, strategy=Z_DEFAULT_STRATEGY[, zdict])

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.. function:: compressobj(level=-1, method=DEFLATED, wbits=MAX_WBITS, memLevel=DEF_MEM_LEVEL, strategy=Z_DEFAULT_STRATEGY[, zdict])

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` Returns a compression object, to be used for compressing data streams that won't

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` fit into memory at once.

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``` *level* is the compression level -- an integer from 0 to 9 or -1.


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``

``` -

A value of ``1`` is fastest and produces the least compression, while a value of

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 ``9`` is slowest and produces the most. ``0`` is no compression. The default

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 value is ``-1`` (Z_DEFAULT_COMPRESSION). Z_DEFAULT_COMPRESSION represents a default

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compromise between speed and compression (currently equivalent to level 6).

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 A value of ``1`` (Z_BEST_SPEED) is fastest and produces the least compression,

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 while a value of ``9`` (Z_BEST_COMPRESSION) is slowest and produces the most.

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 ``0`` (Z_NO_COMPRESSION) is no compression. The default value is ``-1`` (Z_DEFAULT_COMPRESSION).

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Z_DEFAULT_COMPRESSION represents a default compromise between speed and compression

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(currently equivalent to level 6).

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` method is the compression algorithm. Currently, the only supported value is

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``DEFLATED``.

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`` +

:const:DEFLATED.

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` The wbits argument controls the size of the history buffer (or the

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` "window size") used when compressing data, and whether a header and

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trailer is included in the output. It can take several ranges of values:

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trailer is included in the output. It can take several ranges of values,

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 defaulting to ``15`` (MAX_WBITS):

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` * +9 to +15: The base-two logarithm of the window size, which

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` therefore ranges between 512 and 32768. Larger values produce

`@@ -97,7 +99,8 @@ The available exception and functions in this module are:

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` Higher values use more memory, but are faster and produce smaller output.

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` strategy is used to tune the compression algorithm. Possible values are

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 ``Z_DEFAULT_STRATEGY``, ``Z_FILTERED``, and ``Z_HUFFMAN_ONLY``.

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`` +

:const:Z_DEFAULT_STRATEGY, :const:Z_FILTERED, :const:Z_HUFFMAN_ONLY,

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`` +

:const:Z_RLE (zlib 1.2.0.1) and :const:Z_FIXED (zlib 1.2.2.2).

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` zdict is a predefined compression dictionary. This is a sequence of bytes

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`` (such as a :class:bytes object) containing subsequences that are expected

`@@ -175,7 +178,7 @@ The available exception and functions in this module are:

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` .. versionchanged:: 3.6

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` wbits and bufsize can be used as keyword arguments.

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.. function:: decompressobj(wbits=15[, zdict])

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.. function:: decompressobj(wbits=MAX_WBITS[, zdict])

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` Returns a decompression object, to be used for decompressing data streams that

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` won't fit into memory at once.

`@@ -213,13 +216,13 @@ Compression objects support the following methods:

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` All pending input is processed, and a bytes object containing the remaining compressed

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` output is returned. mode can be selected from the constants

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`` -

:const:Z_SYNC_FLUSH, :const:Z_FULL_FLUSH, or :const:Z_FINISH,

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`` -

defaulting to :const:Z_FINISH. :const:Z_SYNC_FLUSH and

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`` -

:const:Z_FULL_FLUSH allow compressing further bytestrings of data, while

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`` -

:const:Z_FINISH finishes the compressed stream and prevents compressing any

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`` -

more data. After calling :meth:flush with mode set to :const:Z_FINISH,

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`` -

the :meth:compress method cannot be called again; the only realistic action is

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to delete the object.

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`` +

:const:Z_NO_FLUSH, :const:Z_PARTIAL_FLUSH, :const:Z_SYNC_FLUSH,

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`` +

:const:Z_FULL_FLUSH, :const:Z_BLOCK (zlib 1.2.3.4), or :const:Z_FINISH,

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`` +

defaulting to :const:Z_FINISH. Except :const:Z_FINISH, all constants

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`` +

allow compressing further bytestrings of data, while :const:Z_FINISH finishes the

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`` +

compressed stream and prevents compressing any more data. After calling :meth:flush

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`` +

with mode set to :const:Z_FINISH, the :meth:compress method cannot be called again;

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the only realistic action is to delete the object.

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`.. method:: Compress.copy()