In a message dated 8/12/2005 8:11:51 AM Pacific Daylight Time,
[EMAIL PROTECTED] writes:
> every so often X runs out of room and there has to be some
> sort of linking or remapping. (Recall we're talking about very large
> strings building up to 50,000 fields (was values).)
> So would it make sense to preallocate the space, then do substring
> assignments, and finally trim it:
>
> X = SPACE( 1000000 ) ;* reserve a million bytes of memory
I learned something !!
No it's true I swear.
I did know that at first string variables are assigned rather small areas to
muck about in. And I knew that as they grew or shrank, these areas were
reassigned or cleaned-up. I actually fell upon this knowledge quite by
accident
when I was writing a Decompiler and a Workspace Analyzer system. I think the
string space originally is just 8 bytes and then gets expanded to 50 then
150...
something like that. At least this was on an ADDS system.
At any rate, it never occurred to me to pre-allocate space. This
certainly would mean that the variable doesnt have to be garbage-collected, at
least
until the program is done.
Also the idea of using sub-string assignment [], instead of <-1> should be
faster, since this would allow a JMP instead of a SCAN. You'd have to keep
track of a PTR for EACH array cell however, not just one for the whole array,
since each cell would have a different LEN.
I believe, in this or a prior thread, it was mentioned that LEN Is
actually a very fast operation, since the length is stored at the head of each
string as a hiddle variable. So perhaps you could try just using LEN instead
of
maintaining a Pointer for each cell ?
Will Johnson
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