World: r3wp

We can currently do default values in R2.

Yup, likely using the same function construction functions as R3 
if you like. Unlike FUNCT and FUNCTOR, that problem doesn't sound 
like it would require anything new to make things easier.

I can already do something like this:


fnc: func [a [unset! string!]][either value? 'a [a][a: "I got value"]]

but it would nice to be able to do something like this:

fnc: func[a [string!] /default $10 ][print a]

fnc 
>> $10

where anything after /default is a default value for the respective 
parameter.

Note that your parameter was the last in the list, the second condition 
mentioned above. That would only work if the calling expression was 
the last in its block because of REBOL's evaluation rules.

Which is even more reason why the second example would be preferred.

The evaluation rules of REBOL can't change without requiring parentheses 
or something around function arguments.

I didn't know how deep changes were being made with respect to R3. 
 Maybe a wish for R4.

Default values for parameters that are not the last parameter would 
need to be made optional using refinements. You *really* can't change 
this, not even in R4.

Seems odd to me.  What language is REBOL written in?

C and REBOL, with some C++ in linked libraries (AGG).

Then it is doable from that standpoint - must be another reason that 
it wouldn't be done.

It has nothing to do with the implementation language though - it's 
a syntax thing.

In C++ for example the defaults are set as follows:

int fnc (int x = 1 int y = 2){...}

I can understand the syntax issue from the perspective of it requiring 
the parameters defaults be ordered.

Languages that wrap function arguments in parentheses (like C and 
Pascal) or are line-oriented (like Basic and Python) or at least 
have statement separators (like ; ) have a way of telling where their 
argument lists end. REBOL can only do so if the arity of a function 
is determinable at the call site. This is the price we pay for getting 
rid of the parentheses.

Yeah, I wish Carl would give more specifics on the internals sometime.

That is not a matter of internals, it really is a consequence of 
REBOL's evaluation rules. You can't change it without changing the 
language in drastically incompatible and slower ways.

Ok, i made a demo using the virtual block scheme (tested only with 
the last alpha)
Sorry for my frenglish
http://www.MegaShare.com/573256

Why you use such a site instead of using for example rebol.org?

it's small.

the scheme size 4,5 Kb, i add documentation, so now it's huge 10 
Kb

Oldes, it's a first try, then i will post it in rebol.org

and i have no ftp currently T_T

Steeve, why does CLEAR clear the whole block?

Don't see nothing there but ads. Steeve, if you want something quick 
you can use mediafire.com

www.mediafire.com

because there is now way to delete one or several records currently

Steeve, ah, forgot that.

Try that link above - it is good.

Paul, try reloading the page a few times. It worked here.

I had to put on compatibility mode but got it.

(but I agree those sites generally suck)

T_T

I'm not sure I'm doing something right as I got an error.  Let me 
look thru the script.

Oh this requires R3 - duh.  I can't try this out yet.

uhuh T_T

I'll check it out in a few months.  ;-)

Steeve, so the basic limitations now are natives that don't support 
ports?

it seems

you can call the actor with his full path anyway, but' it's not rebolish

the main objective it to allow programers, to switch between normal 
blocks and virtual blocks when they want without the need to rewrite 
their code

brb (shower time)

Watch out: R3 currently doesn't support documentation or anything 
other than whitespace (if that) before the REBOL header. Yes, it's 
a bug. You will need to remove the docmentation from the beginning 
of the script for this to run.

Steeve, I notice that there are several comments that start with 
BUG! or MISSING! - I expect to see CureCode tickets for each of these 
:)

Unless you would prefer I write them.

Brian, it's strange i can run the script as-is

Brian write them please i'm a bit lazy with that bugs.

Really? That's new. I'll test that and mark the associated ticket 
as tested if so :)