Binaries
The binary type represents a sequence of bits.
A binary literal looks like << term,… >>.
The simplest term is just a number from 0 to 255. The numbers are stored as successive bytes in the binary.
| | iex> b = << 1, 2, 3 >> |
| | <<1, 2, 3>> |
| | iex> byte_size b |
| | 3 |
| | iex> bit_size b |
| | 24 |
You can specify modifiers to set any term’s size (in bits). This is useful when working with binary formats such as media files and network packets.
| | iex> b = << 1::size(2), 1::size(3) >> # 01 001 |
| | <<9::size(5)>> # = 9 (base 10) |
| | iex> byte_size b |
| | 1 |
| | iex> bit_size b |
| | 5 |
You can store integers, floats, and other binaries in binaries.
| | iex> int = << 1 >> |
| | <<1>> |
| | iex> float = << 2.5 :: float >> |
| | <<64, 4, 0, 0, 0, 0, 0, 0>> |
| | iex> mix = << int ... |
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