World: r3wp

I can't see where someone would want to keep context if they are 
deciding to flatten it to that extreme.

I have a more useful flatten function that encompasses that one that 
will be more useful for someone that wants to keep contexts of no 
so flattened blocks.

It could probably be a mezz as it is very useful

Brian, I'll see if I can whip up my comprehensive flatten function 
to include a context sensitive full flatten and post it here.

Here's a version which modifies in place:

flatten: func [blk [block!] /local rule a b] [
	parse blk [some [a: set b block! (change/part a b 1) :a | skip]]
	blk
]

Nice Brian

I've had to do something like it before. It doesn't preallocate or 
copy, but what can you do.

yeah true

Are they planning to put something like a flatten function in R3?

You can copy/deep first if you like, though that has allocation overhead. 
A version was proposed in the R3 discussions, but hasn't made it 
through the screening process (not general-use enough I guess).

to bad I can see why we need it.

Here's the thing: How often are you going to use it?


We are modularizing REBOL so that you don't have to bundle the whole 
thing together. Functions like FLATTEN would make a great addon module, 
but if the core code doesn't need it, or it's usage would be uncommon, 
it doesn't make the cut.


For that matter, the functions in R3 that I am backporting to R2 
are only those that I have actually seen in regular use in R3 mezzanine 
code. There are some more advanced functions that just won't be making 
it because their design hasn't been settled yet.


Picking something to go into the core is an involved process. And 
you can always make code libraries.

I agree with that.  keep it out and use it as a module.

>> help flatten
USAGE:
    FLATTEN blk /fine /semi /full

DESCRIPTION:
     Returns a new block with desired blocks flattened or removed
     FLATTEN is a function value.

ARGUMENTS:
     blk -- block to flatten (Type: block)

REFINEMENTS:
     /fine -- Flattens blocks to finest representation
     /semi -- Flattens to support 'select operations
     /full -- Flatten fully - ignored with other refinements

flatten: func [

    {Returns a new block with desired blocks flattened or removed}
    blk [block!] "block to flatten"
     /fine "Flattens blocks to finest representation"
     /semi "Flattens to support 'select operations"
     /full "Flatten fully - ignored with other refinements"
     /local blk2
    ][
    blk2: copy []
    fl: func [b][
        either parse b [block!][
            b: first b
            fl b
        ][
            either semi [
                insert tail blk2 b
            ][
                either full [

                    foreach val b [either block? val [fl val][insert tail blk2 val]]
                ][
                    insert/only tail blk2 b
                ]
            ]
        ]
    ]

    if fine [full: none while [parse blk [block!]][blk: first blk]]
    foreach item blk [
        either block? item [fl item][insert tail blk2 item]
    ]    
    blk2
]

>> test: [[1 ["select"]] [2 ["me"]]]
== [[1 ["select"]] [2 ["me"]]]
>> flatten/semi test
== [1 ["select"] 2 ["me"]]

>> test: [[[1 ["Select"]] [[2 ["Me"]]]]]
== [[[1 ["Select"]] [[2 ["Me"]]]]]
>> flatten/fine/semi test
== [1 ["Select"] 2 ["Me"]]

>> test: [[["this"]] [[["is"]]] ['a] 'big [[['mess]]]]
== [[["this"]] [[["is"]]] ['a] 'big [[['mess]]]]
>> flatten/fine test
== [["this"] ["is"] ['a] big ['mess]]

>> test: [[["this"]] [[["is"]]] ['a] 'big [[['mess]]]]
== [[["this"]] [[["is"]]] ['a] 'big [[['mess]]]]
>> flatten/full test
== ["this" "is" a big mess]

I'm not sure I care for the refinement names I chose with the exception 
of /full.  I kinda like that name as it gives me a better perspetive 
of what it is doing.

how can I make object words local to the context of object? I mean

obj: context [a: 1 pri: does [print a]]


I would like to be able to use 'a in the closed context, but I don't 
want it to be available via obj/a ..... I tried to enclose it to 
'use, but then it is not available to 'pri function :-)

See these ML threads on REBOL.org.


http://www.rebol.org/cgi-bin/cgiwrap/rebol/ml-display-thread.r?m=rmlRJCC

http://www.rebol.org/cgi-bin/cgiwrap/rebol/ml-display-thread.r?m=rmlTLVQ

thanks ...

Wrap the USE around the CONTEXT, rather than the other way around.

This topic comes at a good time for me as I have a complex issue 
that I need to address which is similiar to what Pekr's sounds like 
except that I'm binding object/words to object/some-func.  I'm going 
to have the need to not allow someone to access object/words by probing 
object/words.  Object words is to large to have all of it inside 
of object/some-func which is why it is external to that function 
and only parts of it get bound to that some-func.

I just remembered the 'self trick, don't know whether it's officially 
supported, but it works ...

given: ....

o: make object! [ 
	self: make object! [
		p: does [print [a b c d]]
		ca: func [x][a: x]
		d: 4		
	 ]
	a: 1 b: 2 c: 3
]

you have ...

>> o/p
1 2 3 4
>> o/ca 7
== 7
>> o/p
7 2 3 4
>> probe o
make object! [
    p: func [][print [a b c d]]
    ca: func [x][a: x]
    d: 4
]
>> o/a
** Script Error: Invalid path value: a
** Near: o/a
>> o/self/a
** Script Error: Invalid path value: a
** Near: o/self/a

nice that is what I'm looking for.

o/p is directly known? I did not know 'self allows such functionality 
:-)

It's sweet for sure.  Another one of those hidden REBOL perks.

i don't think this is intentional, but it's something i've used quite 
a few times. basically make is returning self, whatever you make 
that be :)

>> make object! [self: "blabla"]
== "blabla"

Objects are kinda strange.  For example, if you set 'self after you 
created the context it can be referenced but remains hidden in a 
sense:

>> obj: context []
>> obj/self: "hidden"
== "hidden"
>> probe obj
make object! [
]
>> obj/self
== "hidden"

But this highly not recommened unless your aware of what your using 
your object for as self will not refer back to itself any longer.

I'd like to thank the 2.7.6 team for all the great new stuff.  In 
particular  Brian Hawley  - well done.  Kudos; the new mezz features 
are awesome.  ALSO and FIRST+ being just two of many that will make 
for more concise code.

Long Live R2.

Perhaps someone can post examples of how the new mezzanines are used 
...

ALSO;   instead of  
    tmp: first series  series: next series  tmp
   also  first series  series: next series

No tmp required,  ALSO  will return the first result of the two expressions 
 BUT in this case why?   :) 
FIRST+;   instead of the (now) useless example I just wrote;

    first+ series    ;; return value at current reference and then advance 
    reference
No tmp, no next required.  All in one expression. 


Note:  SOURCE ALSO   it's cool and will make a lot of sense when 
you see it.

Yeah the mezzanines will be very useful and should be in there just 
because of the frequency they will be used.

also: func [
    {Returns the first value, but also evaluates the second.}
    value1 [any-type!]
    value2 [any-type!]
][
    get/any 'value1
]

so, it's getting the first value .. how is it evaluating the second 
?

also 1 2    1 and 2 are evaluated by the normal sequence of getting 
arguments.   This func captures the two results (simply by having 
them as arguments) and returns the first.   Love the REBOL.  :)

ahh... deep magic

I use the following in my program:

name: any [
	also getname var: yes
	also getanothername var: no
]


if getname fails (returns none) the other function must be called, 
and a variable set to flag this. Could ofcourse be rewritten, but 
I wanted to try using also :)

ahh... deep magic

Made me think of Arthur C. Clarke's 3. law:

Any sufficiently advanced technology is indistinguishable from magic.
:-)

Nah .. it's CS Lewis, and Narnia

I wish we could do something like this:

myfunc: ['notjustanyword [word! [this that]][spec block]

That way we can only pass this or that to the function otherwise 
it generates an error

Maybe I'll add that to the wish list for R4 - lol.

is there any way to check whether the Windows clock has changed?

You can do a call to net time