November 2022: version 4.0.1 released
-------------------------------------
This is a major release which drops support for Python 2.7 and has a new minimum
requirement of Python 3.7. Around 95% of downloads satisfy this - users of
older versions can continue to use bitstring 3.1, which will still be supported
with fixes, but no new features.
Other changes are minimal, with a few features added.
Breaking changes:
-------------------
* Minimum supported Python version is now Python 3.7.
* Removed ConstBitArray and BitString class aliases. Use Bits and BitStream instead.
* The cut() method will now also yield the final bits of a bitstring, even if they
are shorter than the requested cut size.
* Removed default uint interpretation. This wasn't being applied uniformly - default
is now always to return a bitstring object of the given length and not to interpret
it as a uint. Bug 220.
* If an overwrite goes beyond the end of the bitstring it will now extend the bitstring
rather than raise an exception. Bug 148.
New features and improvements:
---------------------------------
* Type hints added throughout the code.
* Underscores are now allowed in strings representing number literals.
* The copy() method now works on Bits as well as BitArray objects.
* The experimental command-line feature is now official. Command-line
parameters are concatenated and a bitstring created from them. If
the final parameter is either an interpretation string or ends with
a ``.`` followed by an interpretation string then that interpretation
of the bitstring will be used when printing it. ::
$ python -m bitstring int:16=-400
0xfe70
$ python -m bitstring float:32=0.2 bin
00111110010011001100110011001101
* New pp() method that pretty-prints the bitstring in various formats - useful
especially in interactive sessions. Thanks to Omer Barak for the suggestion
and discussion.
>>> s.pp()
0: 10001000 01110110 10001110 01110110 11111000 01110110 10000111 00101000
64: 01110010 11111001 10000111 10011000 11110111 10011110 10000111 11111101
128: 11111001 10001100 01111111 10111100 10111111 11011011 11101011 11111011
192: 1100
>>> s.pp('bin, hex')
0: 10001000 01110110 10001110 01110110 11111000 01110110 88 76 8e 76 f8 76
48: 10000111 00101000 01110010 11111001 10000111 10011000 87 28 72 f9 87 98
96: 11110111 10011110 10000111 11111101 11111001 10001100 f7 9e 87 fd f9 8c
144: 01111111 10111100 10111111 11011011 11101011 11111011 7f bc bf db eb fb
192: 1100 c
* Shorter and more versatile properties. The bin, oct, hex, float, uint and int
properties can now be shortened to just their first letter. They can also have
a length in bits after them - allowing Rust-like data types. ::
>>> s = BitArray('0x44961000')
>>> s.h
'44961000'
>>> s.f32
1200.5
>>> s.u
1150685184
>>> s.i7 = -60
>>> s.b
'1000100'
>>> t = Bits('u12=160, u12=120, b=100')
* Support for IEEE 16 bit floats. Floating point types can now be 16 bits long as well
as 32 and 64 bits. This is using the 'e' format from the struct module.
* Support for the bfloat format. This is a specialised 16-bit floating point format
mostly used in machine learning. It is essentially a truncated IEEE 32-bit floating
point number that has the same range but much less accuracy.
* Removed requirement to have a colon before lengths in format strings. So for example
`'uint:12=100'` can be just `'uint12=100'`. The colon is still recommended for
readability if the length isn't given as a number literal.