Why are strings linked lists?

[Ben Escoto]

Hi, can someone tell me why Haskell strings are linked lists?  I have
had some problems with Haskell strings:

1.  Today I spend a few hours trying to track down a memory leak.  It
    turns out I just didn't realize how much space a string takes up.
    On my machine "replicate 5000000 'a'" will use 90MB of space!

2.  They are extremely slow for most operations like writing to disk,
    adding something to the end, concatenation, etc.

3.  They make learning Haskell harder.  Lazy IO functions like
    hGetContents are kind of slick in a shallow way, but I was
    confused about the Haskell IO model because I thought of this as
    the normal way IO was done, not something you could only set up
    through unsafeInterleaveIO or similar.

Python's strings are also immutable, but they work great and are
really convenient.  They are apparently implemented as variable length
arrays.


-- 
Ben Escoto