mailing-list for TeXmacs Users

[Jani Huhtanen <address@hidden>]

On Monday 26 June 2006 19:12, Joris van der Hoeven wrote:
> On Mon, Jun 26, 2006 at 06:21:40PM +0300, Jani Huhtanen wrote:
> > I'm writing my thesis on texmacs, and now at the very last chapter of my
> > thesis I stumbled upon a nasty bug/feature. Texmacs does not load my
> > document anymore. Instead of loading it throws an error:
> >
> > -- TeXmacs] With linked TrueType support
> > ERROR: In procedure scm_allocate_string:
> > ERROR: Argument 1 out of range: 28213052
> >
> > and by staggering coincidence 28213052 (~27Mb) just so happens to be the
> > number of bytes in my document. Please tell me that there is an easy fix
> > to this!
> >
> > Until then I'll try to break the document into parts and edit those
> > instead which is going to be fun :(
>
> This is a problem with Guile, on which TeXmacs is based,
> but which is not part of TeXmacs, so to say.
> In the guile source code, I found
>
>       #define SCM_STRING_MAX_LENGTH ((1UL << 24) - 1UL)
>       #define SCM_STRING_LENGTH(x) ((size_t) (SCM_CELL_WORD_0 (x) >> 8))
>       #define SCM_SET_STRING_LENGTH(s, l) (SCM_SET_CELL_WORD_0 ((s), 
> (((long)
> (l)) << 8) + scm_tc7_string))
>
> This seems to indicate that 2^24 is the maximum allowed length of
> a string (about 16Mb). Of course, this is ridiculous.
> If you are on a 64 bit architecture, then you may check whether
> the following works (recompile Guile and TeXmacs):
>
>       #define SCM_STRING_MAX_LENGTH ((1UL << 56) - 1UL)
>       #define SCM_STRING_LENGTH(x) ((size_t) (SCM_CELL_WORD_0 (x) >> 8))
>       #define SCM_SET_STRING_LENGTH(s, l) (SCM_SET_CELL_WORD_0 ((s), 
> (((long)
> (l)) << 8) + scm_tc7_string))
>
> If that is so, then you are done. This would leave us with the question
> whether the scm_tc7_string really needs to be 8 bits long,
> or whether its size could be decreased to, say, 4 bits.
>
> Best wishes, Joris

I'm not on a 64 bit platform unfortunately. So if I understand this correctly 
TeXmacs stores the documents into a single string. Which is bad for guile 
because guile cannot represent the length of over 16Mb string. Would it be 
possible/easy to store the document in several smaller strings? Perhaps 
one 'part' in a one string.

Other problem which has been partially resolved by working on a one 'part' at 
a time, is that when the text becomes large, editing starts to lag. By lag I 
mean several second freeze up. I don't think it is caused by the autosave 
saving on a background because the lag occurs more frequent that autosave 
should save.

-- 
Jani Huhtanen
TTY Porin yksikkö
address@hidden