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  • > Base84 distinguishes uppercase and lowercase letters, so different encoded names can compare equal on a case-insensitive filesystem.

    I understand for the authors particular application the probability of collision is small, but this makes this encoding completely impractical for filenames generally.

    by cmovq
  • Ridiculous and only tangentially related question, but.... is Base83 uniquely useful in any way?
    by chaps
  • 27% more efficient than base32 at expense of all kind of weird compat issues with shell scripts, etc. Yikes!
    by killerstorm
  • Meanwhile, Windows uses UTF-16 everywhere internally, so "a" and "あ" are both 2 bytes large. You'd still have to exclude surrogate pairs and the Unicode control characters from a filename.
    by Dwedit
  • > How about case-insensitive filesystems? [...] Negligible.

    I don't buy this. Finding collisions is pretty easy. In one repository I have these files:

      rank2.cpp
  rank4.cpp
  rankN.cpp
    The last two have the same case-insensitive Base84 encoding:

      mz{QkARW;1cB
  mz{QkaRW;1cB
    by teo_zero
  • > It emits groups of five characters. Five is the sweet spot: 84⁵ = 4,182,119,424, only 2.6% short of 2³².

    > That leaves enough room for a group to hold 32 bits about 95% of the time on uniformly random input, and 31 bits otherwise.

    > The encoder looks at the next 31 bits. If their value is below 84⁵ - 2³¹, there’s room for a 32nd bit. Otherwise, it consumes just those 31 bits. Either way, the value fits in five base-84 digits.

    Seems pretty awkward.

    by zahlman
  • The non-alphanumeric characters are just asking for trouble. Agents will fail to escape them correctly, and the $ could expand a variable.

    Base62 (or 64, with -_) is totally sufficient.

    by bensyverson
  • > Here’s the alphabet, in encoding order:

    > ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789!#$%&'()+,-;=@[]^_`{}~

    Yeah I definitely don't want any of those last ~22 characters in file names if I need to do anything with them from a shell

    by abound

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