List.ascii_printable-question-mark

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ascii_printable?(list, limit \\ :infinity)

View Source (since 1.6.0)

Specs

ascii_printable?(list(), 0) :: true
ascii_printable?([], limit) :: true when limit: :infinity | pos_integer()
ascii_printable?([...], limit) :: boolean()
when limit: :infinity | pos_integer()

Checks if list is a charlist made only of printable ASCII characters.

Takes an optional limit as a second argument. ascii_printable?/2 only checks the printability of the list up to the limit.

A printable charlist in Elixir contains only the printable characters in the standard seven-bit ASCII character encoding, which are characters ranging from 32 to 126 in decimal notation, plus the following control characters:

  • ?\a - Bell
  • ?\b - Backspace
  • ?\t - Horizontal tab
  • ?\n - Line feed
  • ?\v - Vertical tab
  • ?\f - Form feed
  • ?\r - Carriage return
  • ?\e - Escape

For more information read the Character groups section in the Wikipedia article of the ASCII standard.

Examples

iex> List.ascii_printable?('abc')
true

iex> List.ascii_printable?('abc' ++ [0])
false

iex> List.ascii_printable?('abc' ++ [0], 2)
true

Improper lists are not printable, even if made only of ASCII characters:

iex> List.ascii_printable?('abc' ++ ?d)
false