World: r3wp

2 Andreas:  2 ** 26 limit is hardcoded into checksum/hash function 
IMO, this hash function is used for calculating respective key hashes 
in map! datatype I think, nevertheless this hashing is pretty fast 
and could be used in in-file hashes, there the limit can be theoretically 
limiting. But still 2 ** 26 hash table is pretty huge indeed.

For 2**25 and 2**26 hash table sizes the hash function gives different 
hash numbers, so I think the limit is 2**26 (sorry I missed your 
observation few lines before you are right off course)

Does anyone have any information / Documentation on how to invoke 
a separate R2 program from R3 and/or vice versa?  In other words, 
is it possible to have an R3 script running and start up a separate 
instance of another R2 and/or R3 program to complete some tasks and 
then resume the original script?


Is it possible to time the event to run in a pre-determined amount 
of time?  Say like 5 seconds for the second program to run, if not, 
then show some error message.


What, if any, communications can occur between the programs, passing 
arguments, blocks, files, urls, etc.

You can do that with CALL and communicate via TCP.

Thank you Rebolek -- I'll check that out.

Let's have:
	o: context [a: 1 b: 2]
I can do:
	values-of o ;== [1 2]

Can I update these values somehow to get o == make object! [a: 3 
b: 4]  just using block of values [3 4]?

v: values-of o
... change v ...
set o v

Great... and it is possible in R2 as well.. I'm still learning:)

shortcut:
get o 
== [1 2]

if you want to set an object with another one, better to use
resolve/all o1 o2

I wanted to avoid using objects as an extension's command argument, 
but I decided that it will be more user friendly to use object directly 
anyway... more work on C side, but it worths for it.

Is there a reason why map! does not allow date!, time! or pair! as 
keys?

Is there a reason why codecs (like image loading) are not in host 
part?

Oldes - AFAIK, codecs are going to be completly overhauled. We wanted 
streaming support, and current implementation is imo rather primitive. 
Carl agreed in one roadmap document release, but that file is gone 
(we are waiting for new one). I hope proper port based API will be 
available. So - on one hand it is a good thing it is not part of 
the host-kit, as we arelly need one standardised API, not myriad 
of different hack-ins, but otoh Carl could benefit from some community 
experiments in that regards ....

Just curious: Is there a maximum length to a word name? can you TO-WORD 
a 1 GB string, assuming it's valid?

easily checked with a little powers of two loop ;-0

don't have the memory :-)

have a break :-)

I'm writing docs. Just getting warmed up. :-)

Max word lenth is 255 or 256 in R3

ok, thanks. that's fair enough.

http://www.curecode.org/rebol3/ticket.rsp?id=580&cursor=1

Btw Henrik, I read your GUI R3 code. It's R2 fashioned. You missed 
some R3 tricks. I suppose you already know it though ;-)

Steeve, depends on which parts you read.

I give some examples.

The 'merge-values mezz is actually like the native 'resolve

you use a lot the old idiom
select block 'word 
vs
block/:word (which is faster and more compact)

(sorry it's: select block word)

it's quite possible that some functions are from the original R3 
GUI, long before newer tricks were involved.

Another old R2 idiom:
all [in object 'property object/property]
vs
select object 'property

var: either cond [...][none]
vs
var: if cond [...]

hmm... yes, that is old

But you know, We all are in the same trend, It will take a while 
before we loose old habits

Today, I saw something horrific in an old script of mine.
>> 8 * to-integer v1 + v2 / 8

V1 and V2 are actually integers

(not related specificaly to R3)

I let you think about this coding horror ;-)

Was that R1 semantics? ;-)

I wouldn't always use the IF version in place of EITHER. I generally 
prefer to be explicit.

We use that IF or UNLESS returning none trick a lot. It is used so 
much that it might as well be considered explicit. It is good to 
remember that REBOL doesn't have an optimizer; we have to optimize 
by hand, and the IF trick is faster than the explicit EITHER.

It is used so much that it might as well be considered explicit.

As is my preference for avoiding premature optimization. ;-)

On that note: Steeve...

>> a: [a 1]
== [a 1]
>> a/:b
** Script error: :b has no value
>> select a 'b
== none

It's the same thing as the SELECT object word trick.

Gregg, don't avoid optimization altogether in the name of avoiding 
"premature" optimization :)

A better aphorism to use here would be to avoid being "penny wise 
but pound foolish" - it makes your point better :)

Agreed on optimization being required at times. Not loading lots 
of data? Yes. Using a hash instead of a block? Yes. I have even avoided 
the mezz loop constructs at times, though more often for clarity 
than performance. 


Maybe I'm a special case, but I have rarely found the need to optimize 
my REBOL code for performance at this level. And I can safely say 
I have never ever, ever optimized out EITHER for IF. Since you said 
it's used a lot, what code should I look at to see how and why? I'm 
always happy to see what I've been missing.

It's used in mezzanines, for instance. I tend to just write code 
in micro-optimized form in the first place, since it is easy to do 
and saves you the trouble of doing it later. Even if you are macro-optimizing 
the code (refactoring and such) you tend to use the same micro-optimizations 
in the new code. For that matter, many of the changes and enhancements 
in R3 were done to make micro-optimized code cleaner to read and 
write than they are in R2. But I mostly write library and mezzannine 
code nowadays, so micro-optimization has greater impact than it would 
for user-level code.

Two notes:

- I optimize for code size, using IF, or UNLESS

- the average speed-up looks like being about 27%, though, which 
is worth considering

Interesting: That's the same speedup that referencing words from 
object contexts gives you, relative to function contexts.