Base1 v0.1.0 Base1 View Source

This module encodes and decodes Base1.

Overview

According to the author of Base1:

  Base1 encodes arbitrary binary data as a string of repeated "A" characters.
  With analogy to the unary numeral system, the binary data is encoded in the length of the string.

Base1 is designed to be relatively inefficient, but accurate.

There are three main ways to encode and decode data as Base1 in this module:

Using encode/1 and decode/1 or decode!/1 to produce a sequence of repeated “A” characters. This does not scale.
Using encode_length/1 and decode_length!/1 or decode_length/1. This scales better, though is still relatively inefficient. It is much more compact, however and supports larger inputs.
Using encode_length_bin/1 and decode_length_bin!/1 or decode_length_bin/1. This scales better, but not as well as pure length encoding due to the string conversion. This exists mostly to provide a convenience for interfaces that need Base1 and expect Elixir binary input and output.

Resources

Base 1 Canonical Implementation

Link to this section Summary

Types

base1_binary()

A Base1 encoded binary

Functions

decode!(string)

Decodes a Base1 string as binary

decode(string)

Decodes a Base1 string as binary

decode_length!(number)

Decodes a Base1 string length

decode_length(number)

Decodes a Base1 string length

decode_length_bin!(data)

Decodes a Base1 string length encoded as a string

decode_length_bin(data)

Decodes a Base1 string length encoded as a string

encode!(data)

Encodes a binary as a Base1 string

encode(data)

Encodes a binary as a Base1 string

encode_length(data)

Encodes a binary as a Base1 length

encode_length_bin(data)

Encodes a binary as a Base1 length string

Link to this section Types

base1_binary()

base1_binary() :: <<_::8>>

A Base1 encoded binary.

Link to this section Functions

decode!(string)

decode!(base1_binary()) :: binary()

Decodes a Base1 string as binary.

Raises an ArgumentError if the input string is not a Base1 binary.

Examples

iex> Base1.decode!("A")
<<0>>

iex> Base1.decode!("AA")
<<1>>

iex> Base1.decode!("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA")
"b"

decode(string)

decode(base1_binary()) :: {:ok, binary()} | :error

Decodes a Base1 string as binary.

Returns :error if the input string is not a Base1 binary.

Examples

iex> Base1.decode("A")
{:ok, <<0>>}

iex> Base1.decode("AA")
{:ok, <<1>>}

iex> Base1.decode("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA")
{:ok, "b"}

iex> Base1.decode("AAAAAAHHH BLACK BEAST OF")
:error

decode_length!(number)

decode_length!(non_neg_integer()) :: binary()

Decodes a Base1 string length.

Raises an ArgumentError if the length is not a non-negative integer.

Examples

iex> Base1.decode_length!(1)
<<0>>

iex> Base1.decode_length!(2)
<<1>>

iex> Base1.decode_length!(381115146191751804757868696628784997)
"Hello Cleveland"

iex> Base1.decode_length!(9479543125109159158650175321189934146175361938985120077868441490465756706997907027887945065)
"It is probably better to encode length"

decode_length(number)

decode_length(non_neg_integer()) :: {:ok, binary()} | :error

Decodes a Base1 string length.

Returns :error if the length is not a non-negative integer.

Examples

iex> Base1.decode_length(1)
{:ok, <<0>>}

iex> Base1.decode_length(2)
{:ok, <<1>>}

iex> Base1.decode_length(381115146191751804757868696628784997)
{:ok, "Hello Cleveland"}

iex> Base1.decode_length(9479543125109159158650175321189934146175361938985120077868441490465756706997907027887945065)
{:ok, "It is probably better to encode length"}

iex> Base1.decode_length(-256)
:error

decode_length_bin!(data)

decode_length_bin!(binary()) :: binary()

Decodes a Base1 string length encoded as a string.

Raises an ArgumentError if the length is not a non-negative integer string.

Examples

iex> Base1.decode_length_bin!("1")
<<0>>

iex> Base1.decode_length_bin!("2")
<<1>>

iex> Base1.decode_length_bin!("381115146191751804757868696628784997")
"Hello Cleveland"

iex> Base1.decode_length_bin!("9479543125109159158650175321189934146175361938985120077868441490465756706997907027887945065")
"It is probably better to encode length"

decode_length_bin(data)

decode_length_bin(binary()) :: binary()

Decodes a Base1 string length encoded as a string.

:error is returned if the length is not a non-negative integer string.

Examples

iex> Base1.decode_length_bin("1")
{:ok, <<0>>}

iex> Base1.decode_length_bin("2")
{:ok, <<1>>}

iex> Base1.decode_length_bin("381115146191751804757868696628784997")
{:ok, "Hello Cleveland"}

iex> Base1.decode_length_bin("9479543125109159158650175321189934146175361938985120077868441490465756706997907027887945065")
{:ok, "It is probably better to encode length"}

iex> Base1.decode_length_bin("cheddar cheese please")
:error

encode!(data)

encode!(binary()) :: base1_binary()

Encodes a binary as a Base1 string.

Examples

iex> Base1.encode!(<<1>>)
"AA"

iex> Base1.encode!("b")
"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"

iex> Base1.encode!(<<>>)
<<>>

encode(data)

encode(binary()) :: {:ok, base1_binary()} | :error

Encodes a binary as a Base1 string.

Examples

iex> Base1.encode(<<1>>)
{:ok, "AA"}

iex> Base1.encode("b")
{:ok, "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"}

iex> Base1.encode(<<>>)
{:ok, <<>>}

encode_length(data)

encode_length(binary()) :: non_neg_integer()

Encodes a binary as a Base1 length.

Examples

Base1.encode_length(<<0>>
1

Base1.encode_length(<<1>>)
2

Base1.encode_length("hi")
26986

Base1.encode_length(<<0x03, 0xC0>>)
1217

encode_length_bin(data)

encode_length_bin(binary()) :: binary()

Encodes a binary as a Base1 length string.

Examples

Base1.encode_length_bin(<<0>>
"1"

Base1.encode_length_bin(<<1>>)
"2"

Base1.encode_length_bin("hi")
"26986"

Base1.encode_length_bin(<<0x03, 0xC0>>)
"1217"