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venv/lib/python3.12/site-packages/easybits/__init__.py

@@ -0,0 +1,121 @@
+from bitarray import bitarray
+from bitarray.util import (
+    zeros, 
+    ones, 
+    int2ba,
+    ba2int,
+)
+from easybits.util import is_bit_string
+from easybits.errors import (
+    NotEnoughBits, 
+    IntegersRequireLength, 
+    IntegerAdditionRequiresSameLength,
+)
+
+class Bits(bitarray):
+    """A wrapper around bitarray with a more idiomatic interface for beginners.
+    - Integers are always signed.
+    """
+
+    default_text_encoding = 'ascii'
+
+    @classmethod
+    def zeros(cls, length):
+        return Bits(zeros(length))
+
+    @classmethod
+    def ones(cls, length):
+        return Bits(ones(length))
+
+    def __new__(cls, value=None, length=None, encoding=None):
+        if value is None:
+            bits = bitarray(length or 0)
+        elif isinstance(value, bytes):
+            bits = bitarray()
+            bits.frombytes(value)
+        elif isinstance(value, bool):
+            bits = bitarray([value])
+        elif isinstance(value, int):
+            if not length:
+                raise IntegersRequireLength()
+            bits = int2ba(value, length=length, signed=True)
+        elif isinstance(value, str):
+            if encoding:
+                bits = bitarray()
+                bits.frombytes(value.encode(encoding))
+            elif is_bit_string(value):
+                bits = bitarray(value)
+            else:
+                bits = bitarray()
+                bits.frombytes(value.encode(cls.default_text_encoding))
+        elif isinstance(value, list):
+            bits = bitarray(value)
+        elif isinstance(value, bitarray):
+            bits = value
+        else:
+            raise ValueError(f"Can't create bits from {value}")
+        if length:
+            if length < len(bits):
+                raise NotEnoughBits(value, length)
+            else:
+                sized_bits = bitarray(length)
+                sized_bits[-len(bits):] = bits
+        else:
+            sized_bits = bits
+        return super().__new__(cls, sized_bits)
+
+    def __str__(self):
+        return self.to01()
+
+    def __repr__(self):
+        return self.to01()
+
+    @property
+    def bool(self):
+        return [bool(b) for b in  self.tolist()]
+
+    @property
+    def int(self):
+        return ba2int(self, signed=True)
+
+    @property
+    def bytes(self):
+        return self.tobytes()
+
+    @property
+    def ascii(self):
+        return self.bytes.decode("ascii")
+
+    def __add__(self, other):
+        """Performs bitwise addition on `self` and `other`. Does not
+        check for overflow.
+        """
+        a, b = self, Bits(other)
+        if not len(a) == len(b):
+            raise IntegerAdditionRequiresSameLength()
+        result = Bits.zeros(len(a))
+        carry = 0
+        for i in reversed(range(len(a))):
+            result[i] = a[i] ^ b[i] ^ carry
+            carry = (a[i] & b[i]) | (a[i] & carry) | (b[i] & carry)
+        return result
+
+    def __sub__(self, other):
+        """Performs bitwise subtraction on `self` and `other`. Does not
+        check for overflow.
+        """
+        a, b = self, Bits(other)
+        if not len(a) == len(b):
+            raise IntegerAdditionRequiresSameLength()
+        return a + (-b)
+
+    def __neg__(self):
+        """Treats `self` as an integer, and flips its sign.
+        """
+        if self[0]:
+            return ~self + Bits(1, length=len(self))
+        else:
+            return ~(self + Bits(-1, length=len(self)))
+
+    def concat(self, other):
+        return super().__add__(other)

venv/lib/python3.12/site-packages/easybits/errors.py

@@ -0,0 +1,15 @@
+class BitsError(Exception):
+    message = "Bits error"
+
+    def __str__(self):
+        return self.message
+
+class NotEnoughBits(BitsError):
+    def __init__(self, obj, length):
+        self.message = f"{obj} cannot fit into {length} bits."
+
+class IntegersRequireLength(BitsError):
+    message = "Binary representations of integers require that a length be provided."
+
+class IntegerAdditionRequiresSameLength(BitsError):
+    message = "Can only add integers of the same length."

venv/lib/python3.12/site-packages/easybits/util.py

@@ -0,0 +1,5 @@
+
+def is_bit_string(value):
+    bit_chars = {'1', '0', ' '}
+    return value.strip() and not (set(value) - bit_chars)
+