rle: run-length encoding

_rle_: run-length encoding

Index terms: _rle_ _rle.ss_ _rle.plt_

This is a basic implementation of the standard run-length encoding
algorithm.


Example
-------

    > (require (planet "rle.ss" ("dyoo" "rle.plt" 1)))
    > (rle-encode "110101000111")
    ((2 #\1) (1 #\0) (1 #\1) (1 #\0) (1 #\1) (3 #\0) (3 #\1))
    > (rle-decode (rle-encode "110101000111"))
    "110101000111"

That pretty much sums it up.


API
---

> rle-encode: string -> (listof (list number char))

Returns a list of (number char) sublists representing the run-length
encoding of a-string.


> rle-decode: (listof (list number char)) -> string

Does the inverse of rle-encode: takes a run-length encoding and rehydrates
the string.