World: r3wp

Isn't it shame, that the rewrite function from rebcode* context with 
the userdef-rule is missing in the latest rebcode?

I already found it usefull, here is an example: http://box.lebeda.ws/~hmm/rebol/rc_bunky7.r

As far as I can tell, it's just missing for now. If things go the 
way they have been, it'll be even better when it comes back.

I think, REBCODE will be great for teaching won't it?

Several of my suggestions and comments have been intended to make 
rebcode easier to learn. Easier to use is a side effect.

Porting knut to rebcode? :)

what is knut?

Typo, Knuth. Wrote some legendary programmingbooks, AFAIK he used 
some kind of assembler for examples. :)

Mix

It might be desirable to find out if any feature of his assembler 
is missing. Volunteers?

I don't have the Knuth books, but there is a port of Mix to the .NET 
CLR that I've been meaning to look at.

Does anyone know if Mix supports branches to addresses? Rebcode just 
branches to relative offsets.

see http://sunburn.stanford.edu/~knuth/mmix.html

Technically Mix was the virtual machine, Mixal was its assembler.

It has loads of things for i/o to devices like paper tape....I think 
rebcode could assume that happens as the mezznine level.

i and o could be series parameters

Oldes: the rewriting engine is mezzanine, so it can be easily added 
back by users. i will take care of releasing a script containing 
it as soon as we have an official version out.

so official version will not contain rewriting engine?

that's not decided yet, but probably not.

was it regarded being way too much high-level or so? Or inflexible, 
so that other ppl might find different way of how to aproach this?

the main thing is, that the details need to be discussed more (i.e. 
the grammar for the rules dialect, and things like this).

ok, thanks ...

is there some decimal FLOOR opcode in rebcode, or should I use [to-int 
val to-dec val] instead? Would be FLOOR a good addition?

FLOOR: ROUND can be adapted to Rebcode, but only partially - some 
datatypes aren't available yet, and I have got a newer ROUND version 
- better suited for Rebcodization

I don't need whole ROUND functionality, right now just FLOOR is OK 
for me (but OTOH, ROUND is very useful).

The to-int opcode is equivalent to floor, at least the round-down-to-0 
version of floor. Ceiling can be done by adding 1 (or subtracting 
if the argument is negative).

I did some test with integer conversions and found, that using rebcode 
is 3x faster than using struct! :)

But will rather wait a little bit before making more complex rebcodes, 
it would be good to have some place for rebcode scripts

So they will all be where we can find them when we have to change 
their opcodes after the great rename?

grand rename? :-) it will happen soon, no?

one more link to MMIX: http://sunburn.stanford.edu/~knuth/fasc1.ps.gz

Petr, they say the next version.

Brian: I know I can use to-int but I need decimal value so I'm using 
to-int to-dec. Don't know if native floor would be faster..

Probably not.

Posted to RAMBO:

A SIGN opcode would set a word to the integer -1, 0 or 1 depending 
on whether an argument is less than, equal to, or greater than 0.


sign: ["Set variable to the sign of a value (-1,0,1)" word! word!]


It would be preferable to have SIGN work with all numeric arguments, 
but you might choose to implement this as sign.i and sign.d for speed 
- either way is fine by me. The SIGN opcode, when combined with BRAB, 
would enable functionality equivalent to the BRAS proposal (#3948), 
and so would supercede it. There are many other uses as well.

; Equivalent of BRAS (RAMBO 3948):
sign a x
brab [l0 l1]
; x < 0
label l0
; x = 0
label l1
; x > 0

; Equivalent of CEILING
to-int x
sign a x
add x a

; Equivalent of COMPARE for numbers
set a x
sub a y
sign a a

Is/will be  possible to use apply on function in object! ? Following 
code does not work:

>> ctx: context [rcmul: rebcode [a][mul a 2 return a]]
>> rca: rebcode [a][apply x ctx/rcmul [a] return x]
** User Error: Syntax error: apply x ctx/rcmul [a] return x
** Near: make error! reform [msg copy/part mold/only where 50]

Not sure, we can now take the value of a word? with bind or something? 
and then apply that?

Yes, you can do this:
>> ctx: context [rcmul: rebcode [a][mul a 2 return a]]
>> myrcmul: get in ctx 'rcmul
>> rca: rebcode [a][apply x myrcmul [a] return x]
>> rca 3
== 6


But I think, Kru got a point. It would be better to be able to do 
it his way.

Geomol I thought it's possible this way, but I've got object that 
holds some values plus function for manipulating this values. So 
it's not possible to export my function to global context.

Because I've got lot of this objects (i.e. this object is oscillator 
with settings like pitch and with one rebcode function to produce 
actual value).

Right, and it's not 'nice' to export things to the global context 
like that. We should have it your way! Write it in "RT Q&A".

i thought we have some sort if binding in rebcode now. then it would 
be like

   rebcode[][ set word 'rcmul bind word  ctx  setw x word  apply x [..] 
   ]
but not soure if its really there, and about syntax.

oh

Volker, there's no 'bind in system/internal/rebcodes

Is 1.3.50 current, or is there somthing more new?

1.3.51 28-Oct

I've got 1.3.51