World: r3wp

I am from Czech Republic ....

:D

and when its needed, you can force input types:
fixed a few typos... this should work right:


my-func: func [value /optional opt-value [string!] ] [
	probe value
	if optional [
		print length? opt-value
	]
]

my-func 33
my-func/optional 22 "tadam"
my-func/optional 22 44

the name did seem a bit slav... :D

tnks pasin to my little vault..

pastin

thinking of using objects for the first time, using them to capture 
clinical data for patients.
Need to capture data by time; still just a fuzzy idea.

I have read how you can extend an object by simply redefining it 
with new values, but I wonder if there is a way to REMOVE elements 
from an object?
TIA!

In R2, you can do this:

1. get the body of the object as a block
2. find the word you want to remove
3. remove the word and its value coming right after
4. make a new object from the block

ah!  That makes sense!  Thank you Henrik!  It is good to be working 
(learning) REBOL again, knowing that help is so fast to find on AltMe.

I notice you specified R2 - without asking for details, will this 
be different in R3?

In R3 you have more options for manipulating objects a little bit 
like series, without having to re-make the object, although I'm uncertain 
that you can remove elements from objects. But then you also have 
the map! datatype, which is more suitable for very quick adding and 
removing of key/value pairs.

map!
 ??  so much to learn.  Again, thank you!

http://www.rebol.com/r3/docs/datatypes/map.html


I see it has not yet been documented. I seem to remember that it 
was, but I might be wrong.

You won't be able to remove elements from an object even in R3, because 
it would break binding. But you can create a new object without the 
field, or use a map!, just as Henrik says. Note that you can also 
TRIM objects in R3, which will make a new object based on the old 
one with unset fields and fields set to none not included in the 
new object.

>> trim context [a: 1 b: none]
== make object! [
    a: 1
]
>> trim context [a: 1 b: 2 unset 'b]
== make object! [
    a: 1
]

interesting

BrianH said: "But you can create a new object without the field,...."

Sorry to be especially dense, but do you mean create the new object 
from scratch, or based on the old object?  I've seen the examples 
to create new from old and also adding fields, or resetting the value 
of an existing field, but never excluding old fields.


I look forward to more documentation on "map!"; maybe I should move 
to R3.  Last I checked, there was no GUI in R3, even the Windows 
version, despite what the download page says?


One last newbie question for the day - will there be a 64-bit REBOL? 
 I'm thinking my data could get rather large before too long.  Thanks 
to all of you!

Sorry to be especially dense, but do you mean create the new object 
from scratch, or based on the old object?
 - specially in this case he means the above example

Last I checked, there was no GUI in R3, even the Windows version, 
despite what the download page says?

 there is R3-GUI, which can be downloaded. check the announcements, 
 etc. A new version will be published this week

Hello Ladislav!  That is great news regarding R3-GUI!


Re. BrianH's examples, I read those as specific to the R3 TRIM function, 
so I assumed his other comment referred to some alternative approach. 
 Obviously I have much to learn.  Thank you!

Alternative approach is certainly possible, but the usage of the 
TRIM function looks quite comfortable, I guess.

But only in R3, correct?

Certainly not, this approach (not using the Trim function, though, 
can be emulated in R2

It is possible to define a REBOL function doing that

For example, using the approach Henrik outlined above.

I meant creating a new object from scratch, not based on a direct 
prototype.

For example:
>> x: make object! [a: 1 b: 2 c: 3]
== make object! [
    a: 1
    b: 2
    c: 3
]

>> y: make x [d: 4]  ; creating based on a direct prototype:
== make object! [
    a: 1
    b: 2
    c: 3
    d: 4
]


>> z: make object! head remove/part find body-of x 'b 2  ; making 
based on the body of x, but not directly on x
== make object! [
    a: 1
    c: 3
]

Those will work in R2 as well, and the latter (z) is how you can 
make new objects based on old objects, but with removed fields. You 
can't make an object with fewer fields by direct prototyping, and 
you can't remove fields from existing objects.

Thanks to both Ladislav and Brian for taking the time to make that 
clear!

Hello again!  Cannot see how to make BrianH's example work in REBOL/View 
2.7.8; hungup on how to FIND a set-word:

>> x
>> probe x
make object! [
    a: 1
    b: 2
    c: 3
]
>> z: make object! head remove/part find body-of x 'b 2

** Script Error: head expected series argument of type: series port
** Where: halt-view
** Near: z: make object! head remove/part
>> find body-of x 'b
== none
>> body-of x
== [a: 1 b: 2 c: 3]
>> find body-of x 'b:
== none

Brian's code uses an R3-ism: 'body-of.
Equivalent R2 code looks like this:

     z: make object!  head remove/part find third x to-set-word 'b 2

Thanks Sunanda!  2.7.8 has "body-of"; now I know about using third 
of an object too!  What I was missing was the "to-set-word" - now 
I am off and running again.

Sunanda, BODY-OF was backported to R2 in 2.7.7 :)

Brian .. what was ported is unclear to most people

The real R3ism was the FIND call, unfortunately.
>> body-of context [a: 1 b: 2 c: 3]
== [a: 1 b: 2 c: 3]
>> find body-of context [a: 1 b: 2 c: 3] 'b
== none
>> find body-of context [a: 1 b: 2 c: 3] [b:]
== [b: 2 c: 3]

In R3, the first FIND call would have worked too.

I can't backport the FIND changes in R3 without breaking compatibility, 
so it's going to be a standing difference in the future.

Jack, it is not a good idea to use the ordinal reflectors (third 
object and such) unless you need to run on an old version of R2 (pre-2.7.7 
with R2/Forward not loaded). It makes your code harder to read, and 
less forwards compatible with R3.

In R3 the ordinal reflectors were deliberately removed for security 
purposes (mostly sandboxing).

Thanks Brian!  Duly noted.  If R3 was at least beta, I'd make the 
switch w/o looking back.

New people should check group "Private Groups" for groups, they might 
be interested in to join. And then just ask to be joined, and it 
will happen!

Hello , I am new, just testing this inteface.

welcome!

How can i write a message larger than one line?

Click the "pencil" in the toolbar above the write line.

Thanks

I am an Amiga OS4.1 user, have had some contacts with Rebol when 
it first started up on this "mother" pmlatform and am very happy 
Reboll3 is cominbg back to it.

Any info on when View will be available ? Or can an older version 
of View be used with R3?

I don't think it can be used. It will probably be a while before 
the Amiga version resumes, as Carl, the main developer, is taking 
a break to work on other projects. We need some more development 
on the core of R3 before it can continue.

Again about this interface then

Can i use a bigger font?

I can't reach the resize button to reduce the window somewhatt. How 
can this be done?

Is it possible to do a search in a group or the whole of ta world?

There is an "aA" button next to the "pencil" button, but it varies 
with platform whether it works.

Are you using AltME on AmigaOS4.1?

No there is no AltMe version to download for AOS i am using my wife'sPC

The aA button works fine. I thought it would only affect selected 
text.