OpenEuphoria

Re: Interesting Experiment With String/Sequence Slicing

• Posted by George Walters <gwalters at sc.rr.com> Aug 21, 2001
• 434 views

I agree with this. I've had to write my own in EU... and I'm sure it is slow
compared to a built in function.

...george

----- Original Message -----
From: "Derek Parnell" <ddparnell at bigpond.com>
To: "EUforum" <EUforum at topica.com>
Subject: Re: Interesting Experiment With String/Sequence Slicing


>
> Robert,
> is the *ANY* chance (pretty-lease) that you might create an in-built
version
> of match and find that allows a starting offset index, similar to BASIC's
> instr() function. Maybe somthing like ...
>
>   findfrom(offset, look_for, look_in)
>   matchfrom(offset, look_for, look_in)
>
> I find myself frequently cutting and dicing slices, or doing ssllooww
> searches because this functionality is missing. It would be so much faster
> if these were in-built rather than Euphoria-written functions.
>
> ----- Original Message -----
> From: "Robert Craig" <rds at RapidEuphoria.com>
> To: "EUforum" <EUforum at topica.com>
> Sent: Wednesday, August 22, 2001 2:00 AM
> Subject: Re: Interesting Experiment With String/Sequence Slicing
>
>
> > >
> > Sam Lie writes:
> > > i have ran the profiler and the bottle neck still
> > > shows up when doing string slicing.
> >
> > I gather from your earlier private e-mail that you are reading huge
> > strings from a file and running match() on them.
> > Or perhaps the string *is* the whole file?
> >
> > Since match() starts at the beginning of a sequence,
> > and stops when it encounters a match, I gather
> > you are slicing the 50K strings to look for further matches.
> >
> > Try reading and searching one line at a time using gets().
> > You won't be copying a huge string when you have a match,
> > and you'll make better use of the Pentium on-chip cache,
> > e.g.
> >       object line
> >       integer fn
> >
> >       fn = open("myfile.html", "r")
> >       while 1 do
> >             line = gets(fn)
> >             if atom(line) then
> >                 exit
> >             end if
> >             if match("foobar", line) then
> >                 .....
> >             end if
> >       end while
> >       close(fn)
> >
> > After doing the above, if you are still convinced that
> > slicing is the culprit, you could write your own match()
> > that locates multiple occurrences without slicing.
> > (There may be an example in the mailing list archives.)
> >
> > Regards,
> >    Rob Craig
> >    Rapid Deployment Software
> >    http://www.RapidEuphoria.com
> >
> > >
> > >
> >
> >
>
>
>
>
>