World: r3wp

I really wish the ENLINE/with ticket would be implemented. I could 
use this function daily.

In R3 we have got the

    system/state/last-error


, which is great for convenience. Is there a corresponding variable 
in R2?

If it does not, it would be great to have this feature backported...

Today's Moment of REBOL Zen:

>> s: "A"
== "A"
>> lowercase s
== "a"
>> s
== "a"
>> c: #"A"
== #"A"
>> lowercase c
== #"a"
>> c
== #"A"

:-)

I hope you know why?

Yes, I do.

And I'm thinking, if it would be an idea to let functions like that 
take word arguments handling them like call-by-reference. Then it 
would be possible to change chars too.

You mean also
>> i: 5
== 5
>> multiply i 4
== 20
>> i
== 20 (?)

That would be
	multiply 'i 4

then. Maybe not too useful in that case. Or though, the ++ operation 
(function) could use this too. Which then reminds me, that NEXT should 
be used for what ++ does. :)

There was a discusson in Carl's blog about this long time ago.

move-next 'series
 looks ok but multiply looks weird.
but ++ already works for series as you say.

++ : "Increment an integer or series index."

Has anyone said the following before?

call-by-word

I didn't hear that before.

I suggest: skip ++ and use NEXT with call-by-word to do the same. 
Less functions to remember that way.

using NEXT with call-by-word (I like the name :) ) looks ok to me, 
but I remember that, "guru"s may say "it leads performance overhead 
for next, as it is a native and used a lot. it should check the argument 
and get-value if it is a word."

I'm not too sure about additional overhead, depending on how NEXT 
is implemented today. My guess is, NEXT already test for different 
datatypes, as it can handle blocks, strings, etc. To in that SWITCH 
(guessiong) in the source code, it just have to include the word! 
type also and handle that, and default: give the error.

To -> So

and *guessing* :) Getting late = more typing errors.

Then we could have things like:

>> a: 41
>> next a
== 42
>> a
== 41
>> next 'a
== 42
>> a
== 42

NEXT already test for different datatypes, as it can handle blocks, 
strings, etc.

But it's all series type. So no type checking I think. It supports 
only series and port values.

If it supports those actions, then it should be everywhere:

SKIP, ADD, DIV, NEXT, NEGATIVE, AND etc.. then it leads a overhead.

I would guess, the code is different for doing next string, next 
block and next port.

I like the idea, but it looks it needs using too much GET value in 
all the actions above.

Yeah, and some may argue, it's less readable with call-by-word options. 
But some probably also finds it strange, that NEXT string doesn't 
alter the string, while LOWERCASE string does.

A lot of things like

var: var + something	; or
var: add var something

could be changed to

add 'var something

It's kinda like the += in C.

'var + something
hmm... that's not too readable.

infix functions, op!s should not support this, because it is really 
not readable

Yeah, I tend to agree.

what about writing a bunch of new functions suffixed with '
ADD'
NEXT'

Yes, REBOL makes it possible to do all this already. In fact, all 
the natives could be recreated as mezzanines supporting call-by-name, 
but that'll be slow of course.

You can easily see the extra overhead:
SOURCE ++
additional IF, GET, SET and CASEs..

this should be in all the natives. look too much overhead I think.
Let's wait for comments from gurus.

I'm leaving now. Bye.

ciao

There is a huge speed difference: (my benchmark function executes 
given block 1'000'000 times)
>> i: 0 benchmark [i: i + 1]
== 0:00:00.25
>> i: 0 benchmark [++ i]
== 0:00:02.578

That's more the difference between a native and a mezzanine, than 
the method.

Related is using POKE on e.g. time!:

>> t: 10:20:30
== 10:20:30
>> poke t 2 42
== 10:42:30
>> t
== 10:20:30

But we can change a time using a set-path!:

>> t/2: 42
== 42
>> t
== 10:42:30

So the set-path! way doesn't do the same as POKE in this case.

That was in R2. In R3, POKE can't handle time!

And that's probably an ok decision.

That's more the difference between a native and a mezzanine, than 
the method.
 - That's right.

From R3, where ++ is native::

>> dt [loop 10000000 [i: i + 1]]
== 0:00:01.90374
>> dt [loop 10000000 [++ i]]
== 0:00:01.011743

Try it in R3:
>> dt [i: 0 loop 1000 [i: i + 1]]
== 0:00:00.000251
>> dt [i: 0 loop 1000 [++ i]]
== 0:00:00.000383


Then the difference is more due to the code in ++ to tell whether 
i is an integer or a series

Hm, try do more loops on your system, Brian.

Weirdly enough, I think that it might be faster sometimes depending 
on what is going on in the background.

Nope, consistently faster. No interpreter overhead.

>> dt [i: 0 loop 100000 [i: i + 1]]
== 0:00:00.041421
>> dt [i: 0 loop 100000 [++ i]]
== 0:00:00.022857
>> dt [i: 0 loop 1000000 [i: i + 1]]
== 0:00:00.205488
>> dt [i: 0 loop 1000000 [++ i]]
== 0:00:00.130813

Yes, ++ is faster, contrary to your first test.

And it makes sense.