Re: Internal Representation of Strings

"Tony" <tony@my.net> wrote in message
> "Chris F Clark" <cfc@shell01.TheWorld.com> wrote in message
>>> What are some good ways/concepts of internal string representation?
>>
>> One such pointer is this (old but valuable) paper by Paul Abrahams:
>>
>> http://delivery.acm.org/10.1145/60000/51610/p61-abrahams.pdf?key1=51610&key2=4789464321&coll=GUIDE&dl=GUIDE&CFID=21920990&CFTOKEN=76966469
>
> The replies to my OP are appreciated. At this point in my research, I
> know that null-terminated implementation (maybe just for
> literals?). I'm leaning toward a Pascal-style string but with either a
> 32-bit length or 7/16/32-bit lengths.


I'm thinking of the following representation for short strings 2 to 256
characters, designed for use as array and record elements.


The short strings have a fixed maximum size, but can contain a shorter
string within that. I'd like to store a length but don't want to sacrifice a
byte (the string might only be 8 chars for example). So I store the length
using the final two bytes as follows, for a string with 8 bytes:


0,0 Length is 0
0,N Length is N (up to 6)
X,0 Length is 7
X,Y Length is 8


(But: needs a bit of logic to translate to the Ptr+Length form used
everywhere else. And doesn't allow embedded zeros)


--
Bartc
[This sounds awfully complicated for an in-memory design. Why not just
use a four byte length and code more compactly if needed on I/O. -John]

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