A binary is a contiguous sequence of bytes. Elixir has no dedicated string type, so double-quoted strings are binaries underneath and can be concatenated with <>. section 2.4.7 section 2.4.8
Build and use binary strings with these core operations:
- Construct byte sequences with <<...>>; values exceeding one byte are truncated unless an explicit bit size is supplied. section 2.4.7
- Combine binaries with <> and use interpolation, escapes, sigils, and heredocs for string syntax. section 2.4.8
- Prefer binary strings over character lists for ordinary text; use String functions for character-oriented operations. section 2.4.8
- Use binary pattern matching to extract bytes, bit fields, or a suffix beginning after a known binary prefix. section 3.1.7
Parse a command prefix
command = "ping www.example.com" "ping " <> url = command url # "www.example.com" section 3.1.7
iex(8)> <<1, 2>> <> <<3, 4>> <<1, 2, 3, 4>>
Concatenate binary values directly and inspect the resulting byte sequence. section 2.4.7
iex(3)> iolist = [] #1 iolist = [iolist, "This"] #2 iolist = [iolist, " is"] #2 iolist = [iolist, " an"] #2 iolist = [iolist, " IO list."] #2 [[[[[], "This"], " is"], " an"], " IO list."] #3
Assemble output incrementally with nested IO lists when repeated binary construction would be inefficient. section 2.4.12
