Packing a simple dictionary into a string - extending struct?

[Jonathan Fine]

John Machin wrote:

> def unpack(bytes, unpack_entry=unpack_entry):
>     '''Return dictionary gotten by unpacking supplied bytes.
>     Both keys and values in the returned dictionary are byte-strings.
>     '''
>     bytedict = {}
>     ptr = 0
>     while 1:
>         key, val, ptr = unpack_entry(bytes, ptr)
>         bytedict[key] = val
>         if ptr == len(bytes):
>                 break
> # That's beautiful code -- as pretty as a cane-toad.

Well, it's nearly right.  It has a transposition error.

> # Well-behaved too, a very elegant response to unpack(pack({}))

Yes, you're right.  An attempt to read bytes that aren't there.

> # Try this:
>     blen = len(bytes)
>     while ptr < blen:
>         key, val, ptr = unpack_entry(bytes, ptr)
>         bytedict[key] = val
> 
>     return bytedict

I've committed such a change.  Thank you.

-- 
Jonathan