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Struct `std.bitmanip.BitArray`

A dynamic array of bits. Each bit in a BitArray can be manipulated individually or by the standard bitwise operators &, |, ^, ~, >>, << and also by other effective member functions; most of them work relative to the BitArray's dimension (see dim), instead of its length.


						
				struct BitArray
				;

Constructors

Name	Description
`this` ()	Creates a `BitArray` from a `bool` array, such that `bool` values read from left to right correspond to subsequent bits in the `BitArray`.
`this` (v, numbits)	Creates a `BitArray` from the raw contents of the source array. The source array is not copied but simply acts as the underlying array of bits, which stores data as `size_t` units.

Properties

Name	Type	Description
`dim`[get]	`ulong`
`dup`[get]	`BitArray`	Duplicates the `BitArray` and its contents.
`length`[get]	`ulong`
`length`[set]	`ulong`	Sets the amount of bits in the `BitArray`. Warning: increasing length may overwrite bits in the final word of the current underlying data regardless of whether it is shared between BitArray objects. i.e. D dynamic array extension semantics are not followed.
`reverse`[get]	`BitArray`	Reverses the bits of the `BitArray`.
`sort`[get]	`BitArray`	Sorts the `BitArray`'s elements.

Methods

Name	Description
`bitsSet` ()	Return a lazy range of the indices of set bits.
`count` ()	Counts all the set bits in the `BitArray`
`flip` ()	Flips all the bits in the `BitArray`
`flip` (pos)	Flips a single bit, specified by `pos`
`opApply` (dg)	Support for `foreach` loops for `BitArray`.
`opBinary` (e2)	Support for binary bitwise operators for `BitArray`.
`opBinary` (b)	Support for binary operator ~ for `BitArray`.
`opBinaryRight` (b)	Support for binary operator ~ for `BitArray`.
`opCast` ()	Convert to `void[]`.
`opCast` ()	Convert to `size_t[]`.
`opCmp` (a2)	Supports comparison operators for `BitArray`.
`opEquals` (a2)	Support for operators == and != for `BitArray`.
`opIndex` (i)	Gets the `i`'th bit in the `BitArray`.
`opIndexAssign` (b, i)	Sets the `i`'th bit in the `BitArray`.
`opOpAssign` (e2)	Support for operator op= for `BitArray`.
`opOpAssign` (b)	Support for operator ~= for `BitArray`. Warning: This will overwrite a bit in the final word of the current underlying data regardless of whether it is shared between BitArray objects. i.e. D dynamic array concatenation semantics are not followed
`opOpAssign` (nbits)	Operator `>>=` support.
`opOpAssign` (nbits)	Operator `<<=` support.
`opSliceAssign` (val)	Sets all the values in the `BitArray` to the value specified by `val`.
`opSliceAssign` (val, start, end)	Sets the bits of a slice of `BitArray` starting at index `start` and ends at index ($D end - 1) with the values specified by `val`.
`opUnary` ()	Support for unary operator ~ for `BitArray`.
`toHash` ()	Support for hashing for `BitArray`.
`toString` (sink, fmt)	Return a string representation of this BitArray.

Example

Slicing & bitsSet

import std.algorithm.comparison : equal;
import std.range : iota;

bool[] buf = new bool[64 * 3];
buf[0 .. 64] = true;
BitArray b = BitArray(buf);
assert(b.bitsSet.equal(iota(0, 64)));
b <<= 64;
assert(b.bitsSet.equal(iota(64, 128)));

Example

Concatenation and appending

import std.algorithm.comparison : equal;

auto b = BitArray([1, 0]);
b ~= true;
writeln(b[2]); // 1
b ~= BitArray([0, 1]);
auto c = BitArray([1, 0, 1, 0, 1]);
writeln(b); // c
assert(b.bitsSet.equal([0, 2, 4]));

Example

Bit flipping

import std.algorithm.comparison : equal;

auto b = BitArray([1, 1, 0, 1]);
b &= BitArray([0, 1, 1, 0]);
assert(b.bitsSet.equal([1]));
b.flip;
assert(b.bitsSet.equal([0, 2, 3]));

Example

String format of bitarrays

import std.format : format;
auto b = BitArray([1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1]);
writeln(format("%b", b)); // "1_00001111_00001111"

Example

import std.format : format;

BitArray b;

b = BitArray([]);
writeln(format("%s", b)); // "[]"
assert(format("%b", b) is null);

b = BitArray([1]);
writeln(format("%s", b)); // "[1]"
writeln(format("%b", b)); // "1"

b = BitArray([0, 0, 0, 0]);
writeln(format("%b", b)); // "0000"

b = BitArray([0, 0, 0, 0, 1, 1, 1, 1]);
writeln(format("%s", b)); // "[0, 0, 0, 0, 1, 1, 1, 1]"
writeln(format("%b", b)); // "00001111"

b = BitArray([0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1]);
writeln(format("%s", b)); // "[0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1]"
writeln(format("%b", b)); // "00001111_00001111"

b = BitArray([1, 0, 0, 0, 0, 1, 1, 1, 1]);
writeln(format("%b", b)); // "1_00001111"

b = BitArray([1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1]);
writeln(format("%b", b)); // "1_00001111_00001111"

Authors

Walter Bright, Andrei Alexandrescu, Jonathan M Davis, Alex Rønne Petersen, Damian Ziemba, Amaury SECHET

License

Boost License 1.0.

API Documentation

Struct std.bitmanip.BitArray

Constructors

Properties

Methods

Example

Example

Example

Example

Example

Authors

License

Struct `std.bitmanip.BitArray`