AltME groups: search

in R2,  the best way is to set a word to the value you're evaluating, 
and conditional to that value's pass/fail, you switch the following 
rule to allow it to continue or track back, so it matches another 
rule.


here is a rather verbose example.  note that this can be tweaked 
to be a shorter rule, but it becomes hard to map out how each part 
of the rules relate.. here, each part is clearly layed out.

rebol []


pass-rule: [none]
fail-rule: [thru end]

condition-rule: pass-rule



parse [
	word-a
	"ere"
	835
	word-b
	15
	word
	86
	bullshit
	#doglieru3
	word-c
][
	any [
		
		[
			; this rule only matches words ending with "-?"
			set val word! 
			[
				[
					(
						val: to-string val
						either #"-" = pick (back back tail val) 1  [
							condition-rule: pass-rule
						][
							condition-rule: fail-rule
						]
					)
					condition-rule
					(print ["PATTERN WORD:" val])
				]
				|[
					(print ["Arbitrary word: " val])
				]
			]
		]
		
		| skip
	]
]

ask ""

as follows: 

entities-map: make map! []
foreach entity entities-block [entities-map/:entity: true]

By the way, the backports include FUNCT, closures (faked), typesets 
(faked), the REFLECT and *-OF functions, APPLY, MAP-EACH, ...

I used latest R2 to do experiment something with rebol yesterday.. 
I saw the map-each function but I didn't find the accumulate . Is 
it under some other name maybe?

it's a little less nice looking but it would be more uniform and 
logical .. the way of "least surprise"


because now when you write your own functions liek map-each you don't 
know or make it look like foreach with or make all custom functions 
not accept active words which makes your code more systematic and 
easyer to understand , but then your function is not in style with 
rebol's foreach forall ..etc

Since there are mezzanines for them already, it's not a problem (though 
the ASSERT mezzanine still sucks). Same with MAP-EACH.

Geomol - Cyphre told me, that you could map parts of AGG to HW acceleration, 
but then it can look differently on each gfx card/driver ..

they are REBOL plugins.  you must map the libwmp3.dll  or libwmp3.lib 
 inside of the extension...

tombon:  the thing is that rebol has to map its datatypes to the 
basic and static data representations of C and other compiled languages. 
 the R2 tried to do this within rebol, but it ended-up being useless 
for many libs which used types that rebol cannot translate natively... 
like unsigned integers or single precision floats, arrays... etc.


extensions do the rebol datatype conversion in the C side, so that 
it can directly map ANY C code to a form that rebol functions can 
understand directly  and vice versa... so for now we could use blocks 
as an interface for structs, even though R3 doesn't understand anything 
about structs.  :-)  


Its MUCH faster to map in C and makes the lib completely integrated 
into REBOL when used.


So for example, we can use tuples as colors within REBOL, and the 
DLL's functions will be called with a struct  or an array, to map 
the 3 channels.

I also thought of a very neat way to map c methods and struct access 
 :-)

I try to keep this as short as possible.

Imagine you have this file, called %test.r:

==file==

REBOL[
    Title: {Simple extension test}
	Name: ext-test
	Type: extension
	Exports: []
]

map-words: command []{
    word_ids = RXI_MAP_WORDS(RXA_SERIES(frm, 1));
    return RXR_TRUE;
}

fibc: command[
    len [integer!]
]{
    RXA_TYPE(frm, 1) = RXT_INTEGER;

    i64 o = 0;
    i64 l = RXA_INT64(frm, 1);
    i64 i;

    for (i = 0; i <= l; i++)
        o = o + i;

    RXA_INT64(frm, 1) = o;

    return RXR_VALUE;
}

add5: command [
    a [integer!]
][
    a: a + 5
    return a
]

==end of file==


And now imagine that in R3 console you are in the directory where 
you have the file %test.r .
Now you type:

>> compile %test.r
>> import %test.dll
>> fibc 10
== 55
>> add5 5
== 10

And that's all.


If you want to try it, you need to have TCC (TinyC Compiler) - get 
it from http://download.savannah.nongnu.org/releases/tinycc/tcc-0.9.25-win32-bin.zip
The script expects it instaled to %/c/tcc/ but it can be changed.
Then go to r3 console and type:

>> do http://box.lebeda.ws/~rebolek/rebol/srec.rip
>> cd %srec/
>> do %srec.r


Then you can try COMPILE etc. (see above). %test.r is included in 
the archive.

SREC is shortcut for Simple REBOL Extension Compiler.
    
Enjoy! (if it works ;)

brian, yes we can add our own devices... in fact, it seems quite 
easy, and I will probably be adding a DB trigger device within a 
week or two.  :-)


the thing is that there aren't any exposed or documented *native* 
hooks from the host into the core... 


so far, I've got a callback library (called wire) working which executes 
rebol code in global context using the Reb_Do_String() r3lib.dll 
exported function  :-)


now I just need to use that library within the extension and see 
how it goes... the moment I have *something* which works... I'll 
stop improving the hack... from there on, I'll just work on the architecture 
of the caller and callee, to see how we could make it simple and 
easy to setup, from the extension and within the application using 
that extension... generically.


the code in between can change completely, it wouldn't actually change 
the extension or application code (that's the idea anyways)... just 
a few includes and headers which map how to link to the callback 
system.  I'll also try to build a device, just to see how that can 
be used instead of callbacks... but I still need to use a callback 
from the extension in order to access the host... so for now my hack 
is essential, whatever I do.


in this case, I'll be dispatching the GLUT events within the rebol 
using this architecture... I should have an interactive OpenGL window 
by tomorrow... crossing my fingers.


for now I am busy rebuilding my old OpenGL project within the new 
cleaned-up MSVS solution I've been working on for 2 days now... there 
are soooo many properties, its scary and long to setup... especially 
in this setup where there are several interdependent projects within 
the solution... but now, at least, when I change stuff at any layer 
and build, it builds all the stuff correctly in one step...

anyhow.  I wonder, can anyone tell me if its easy to load dll and 
map functions dynamically on LINUX?

so did anyone start on the R3 /library  extension?  if not I can 
work on that for windows, and make it so its very easy for someone 
else to map it to linux ( as a few stubs to re-implement  ).

hehehe  I'll do my first tests, and then I'll see If I can wrap the 
platform-specifc parts of the process through dyncall's source code. 
 this way we will be able to compile the /library extension for any 
platform without any source code changes.


my design is to use header file macros which actually map the calling 
conventions based on your platform... THAT I can definitely borrow 
from dyncall if it BSD licensed :-)

Has some useful new ext funcs:

	void *(*make_block)(u32 size);
	void *(*make_string)(u32 size, int unicode);
	int (*get_string)(REBSER *series, u32 index, void **str);
	u32 (*map_word)(REBYTE *string);
	u32 *(*map_words)(REBSER *series);
	REBYTE *(*word_string)(u32 word);
	u32 (*find_word)(u32 *words, u32 word);
	int (*series_info)(REBSER *series, REBCNT what);
	int (*get_char)(REBSER *series, u32 index);
	u32 (*set_char)(REBSER *series, u32 index, u32 chr);
	int (*get_value)(REBSER *series, u32 index, RXIARG *val);

 int (*set_value)(REBSER *series, u32 index, RXIARG val, int type);
	u32 *(*words_of_object)(REBSER *obj);
	int (*get_field)(REBSER *obj, u32 word, RXIARG *val);
	int (*set_field)(REBSER *obj, u32 word, RXIARG val, int type);

one fun thing is that we do not have to use the C source types as 
the interfaces for the commands.

my next test is to build a generic object to parameter map.

so, if you have a C func declared as:
int myFunc (int a, int b)

you'll be able to call it from rebol using:

obj: context [a: 1 b: 2]
myFunc obj

The external sample extension works partly (apart from several string 
and word functions, like t-word-map)I understand that I have to recompile, 
but  it's not so easy to find the proper headers. Furthermore, I 
am not sure that the old make-ext.r script which generates the init_block 
is still usable. It would be useful to actualize the external sample 
extension. By the way, where is the page giving the main changes 
from a101 (changes from char * to REBSER*, t-word-map etc) ? I am 
not able to find it out.

My personal summary for the extensions API:

- A100 is basically the same as the previous extensions-only API 
release (A77).

- A101 adds map_word, word_of_string, words_of_object, get_field, 
set_field

- A102 adds make_image and gc_protect, renames the constants used 
for series_info from RXI_INFO_* to RXI_SER_* and adds RXI_SER_DATA

http://www.rebol.com/r3/docs/concepts/extensions-making.html#section-17
says it's out of date and I'm really having trouble including words 
as symbols in a result block of an extension command. 

It works fine with an *INIT_BLOCK defined as


 const char *init_block = "REBOL [\nTitle: {Power Management}\nName: 
 power\nType: extension\nExports: [power-status]\n]\n"

     "lib-boot:           does [map-words words] ;-- Is that a good idea?\n"

     "words:             [ac-line battery remains of high low critical 
     charging]\n"
	    "map-words:    command [words [block!]]\n"
	    "power-status: command []\n"
;

if after IMPORT %power.dll I call SYSTEM/MODULES/POWER/LIB-BOOT.


Is there a way to have IMPORT automatically execute the LIB-BOOT 
code with a simple extension not included into the host code with 
host-kit?

I'm trying to return a block containg a word not taken from a commands 
arguments. Say, I want to return a block like [BATTERY CHARGING]: 

That works with

	u32 *word_ids = 0; // used to hold word identifiers
	enum power_words {W_POWER_BATTERY = 1, W_POWER_CHARGING};

	RXIEXT int RX_Call(int cmd, RXIFRM *frm, void *data) {
		/* .... */

		v.int32a = word_ids[W_POWER_BATTERY];
		RXI_SET_VALUE(s, pos++, v, RXT_WORD); 
		v.int32a = word_ids[W_POWER_CHARGING];
		RXI_SET_VALUE(s, pos++, v, RXT_WORD);
	
		/* .... */
   	}


only after importing the DLL I "manually" init the words with a MAP-WORDS 
command. I was thinking that IMPORT eventually triggers LIB-BOOT 
init-code from the INIT_BLOCK. It seems like the init code is not 
executed.

That MAP-WORDS command only does:

	word_ids = RXI_MAP_WORDS(RXA_SERIES(frm, 1));
	return RXR_TRUE;

Ouch! Now that problem above has a really simple solution: Just putting 
the module init code in the CONST CHAR *INIT_BLOCK works great:

	const char *init_block =
	    "REBOL [\n"
	        "Title:   {Power Management}\n"
	        "Name:    power\n"
	        "Type:    extension\n"
	        "Exports: [power-status capture-screen]\n"
	    "]\n"

     "words:          [ac-line battery remains of high low critical charging]\n"
	    "map-words:      command [words [block!]]\n"

     "power-status:   command [{Returns ac-line and battery status information.}]\n"

     "capture-screen: command [{Returns screenshot as an image.}]\n"
	    "map-words words\n";


The "magic" is the last line, where MAP_WORDS WORDS is evaluated 
ofter loading the module, that command inits the dll with the word 
ids used by the extension.

Not sure If that's what you're after, but anyways ...

---- REBOL side ----
convert: command [value [number!] unit [word!]]

---- C side ----
if (unit == RL_MAP_WORD("ppi")) {
    // do something
} 
elseif (unit == RL_MAP_WORD("ppcm")) {
    // do some other thing
}

Do you get the idea?
>> convert 18 'ppi
>> convert 20 'ppcm

Would that work? Is it even proper C?

typedef enum {
    PixelsPerInchResolution = RL_MAP_WORD("ppi"),
    PixelsPerCentimeterResolution = RL_MAP_WORD("ppcm"),
    ...     
}

if (unit == RL_MAP_WORD("PixelsPerInchResolution")) {
    SomeFunc(PixelsPerInchResolution);
} 
elseif (unit == RL_MAP_WORD("PixelsPerCentimeterResolution")) {
    SomeFunc(PixelsPerCentimeterResolution);
}
else {
    SomeFunc(UndefinedResolution);    
}

it just looks strange.

I was about to suggest 

RXIEXT int SomeFunc(RXIFRM *frm) {
    int unit = RL_GET_VALUE(frm, 0, RXT_WORD);

    if (unit == RL_MAP_WORD("PixelsPerInchResolution")) {
    }

    elseif (unit == RL_MAP_WORD("PixelsPerCentimeterResolution")) {
    }
    else {
    }      
}

How is the above superior to

---- REBOL ----
some-func 'pixels-per-centimeter-resolution

---- C ----
if (unit == RL_MAP_WORD("pixels-per-centimeter-resolution") {
    SomeFunc(unit);
    return RXR_TRUE;
}

But a dialected approach like


>> some-func: func [unit [word!]] [select [pixels-per-inch-resolution 
1 pixels-per-centimeter-resolution 2] unit] 


does look ok to me, though. At least, that way, assigning other numerical 
values to the "keywords" wouldn't harm.

the problem with the above is, that in A110:
words: [pixels-per-centimeter-resolution]
export testword: command ['wrd [lit-word!]]
...
case testword: {
   int unit = RL_MAP_WORD("pixels-per-centimeter-resolution");
   RL->print("int: %d\n", unit);
}

prints int: 1399  = something what I don't expect :)

with:
case CMD_GRAPHICS_INIT_WORDS:
        //temp hack - will be removed later
        graphics_ext_words = RL_MAP_WORDS(RXA_SERIES(frm,1));
        break;

Here's how I explained to myself how things went:


With A102, the time I started playing around with extensions, there 
was this RL_FIND_WORD which is supposed to map words against an "extension 
local" word block. But sadly, I never got that working.

It was the "temp hack" comment from which I concluded that the preferred 
method then became RL_MAP_WORD, which maps a word to a global word 
id, hence the 1381 number you've got yesterday. With that, you don't 
need to ENUM in your code but can just compare words supplied with 
words known.


But, I may be totally off track with that reasoning ... wouldn't 
take me any wonder :-)

Kaj, here's an example %rebol.r for your scenario:

REBOL []
use [sys-path] [
sys-path:  %/some/safe/directory/full/of/extensions/
sys/load-module/delay map-each x read sys-path [sys-path/:x]
]

Remember, on many Linuxes you just want to load libc, but the actual 
file is something like libc.so.6 or something (I'm paraphrasing here). 
Having LOAD-EXTENSION translate .rx is no different from that. You 
can even have a filename map on your platform if you like.

Or is there a better way to map the error message back to the source 
file?

Not in conjunction with RL_Words_Of_Object, but RL_MAP_WORD, e.g.:

type = RL_GET_FIELD(database, RL_MAP_WORD("connection"), &value);
...
value.addr = henv;

RL_SET_FIELD(database, RL_MAP_WORD("environment"), value, RXT_HANDLE);

For callbacks to set the callback function, your C code must have 
a pointer to the object where it resides (an object you made or some 
other system context) and the name of the function, as a word id.

Those need to be set in the CBI structure:
cbi->obj = obj;
cbi->word = word;


The word ID can be retrieved with RL_MAP_WORD. And a self created 
context in the same way. But how do I rerieve the ID of the global 
context (do we still have such a thing?)?

There are no context IDs and there's no need for RL_MAP_WORD. RXA_WORD 
handles that

I've spent a bit of time going over R3/View and believe it now has 
all the "building blocks" required to build a modern/fast gob! based 
GUI. The amazing thing is that these building blocks are the 10 natives 
that View adds [to Core]. They are:

	gob!
	caret-to-offset
	cursor
	draw
	effect
	map-event
	map-gob-offset
	offset-to-caret
	show
	size-text


With these 10 natives (gob! is actually a type!) we should be able 
to construct simple but powerfull gob!-based GUIs with a smaller 
mezz footprint than R2. My preliminary conversion of RebGUI to R3 
seems to take about 50% the code to do the same thing [compared to 
R2] ... very promising at first glance.


To get a feeling for how tight the code can be the next post is the 
entire [skeleton] source of a working gob!-based GUI.

ctx-rebgui3: make object! [

	cursors: make object! [
		app-start: 32650
		hand: 32649
		help: 32651
		hourglass: 32650
		arrow: 32512
		cross: 32515
		i-shape: 32513
		no: 32648
		size-all: 32646
		size-nesw: 32643
		size-ns: 32645
		size-nwse: 32642
		size-we: 32644
		up-arrow: 32516
		wait: 32514
	]

	colors: make object! [
		page: white
		edit: white
		text: black
		true: leaf
		false: red
		link: blue
		theme: [165.217.246 0.105.207 0.55.155]
		outline: [207.207.207 160.160.160 112.112.112]
	]

	metrics: make object! [
		cell: 4
		gap: cell * 2
		line: cell * 5
		margin: cell * 4
		margin-size: as-pair margin margin
		radius: 2
	]

	;	Private functions

	set 'make-gob make function! [[

  spec [block!] ; offset, size and one or more attribute/value pairs
		/data object
		/local size text gob axis
	][
		size: spec/2
		if any [negative? size/x negative? size/y] [
			text: select spec 'text
			all [block? text text: first find text string!]

   size: 8x4 + size-text make gob! compose [size: 9999x9999 text: (text)]
			all [negative? spec/2/x spec/2/x: size/x]
			all [negative? spec/2/y spec/2/y: size/y]
		]
		gob: copy []
		;	attributes are (text, color, effect, image and draw)
		foreach [attribute value] spec [
			switch attribute [
				box [
					attribute: 'draw
					value: compose [
						pen (get value/1)
						line-width 1
						fill-pen (get value/2)
						box 0x0 (spec/2 - 1x1) (metrics/radius)
					]
				]
				pill [
					attribute: 'draw
					axis: either spec/2/x >= spec/2/y [2] [1]
					value: compose/deep [
						pen (colors/outline/3)
						line-width 1

      grad-pen linear (spec/2/:axis * .1) (spec/2/:axis * .9) (all [axis 
      = 2 90]) [(colors/outline/1) (white) (colors/outline/1)]
						box 0x0 (spec/2 - 1x1) (metrics/radius)
					]
				]
			]
			append gob reduce [attribute value]
		]
		spec: gob

  gob: make gob! compose [offset: spec/1 size: spec/2 (to set-word! 
  spec/3) spec/4 data: (make object! any [object copy []])]
		foreach [attribute value] skip spec 2 [

   append gob make gob! compose [offset: 0x0 size: spec/2 (to set-word! 
   attribute) value]
		]
		gob
	]]

	;	Public functions

	set 'display make function! [[
		title spec

  /local gob xy max-x max-y left-to-right? after-count after-limit 
  here arg append-widget widget last-widget word
		action
		handler
		size
		text
		color
	][
		xy: metrics/margin-size
		max-x: xy/x
		max-y: xy/y
		left-to-right?: true
		after-count: 1
		after-limit: 9999
		
		gob: make gob! compose [text: (title) data: (make object! [])]

		append-widget: make function! [[][
			unless widget [exit]
			unless handler [

    handler: compose/deep [on-down: make function! [[event][(action)]]]
			]
			append gob switch widget [
				bar [

     make-gob compose [(xy) (as-pair max-x - metrics/margin 1) color (colors/outline/3)]
				]
				button [
					all [none? size size: 15x5]

     make-gob/data compose/deep [(xy) (size * metrics/cell) pill none 
     text [center (text)]] handler
				]
				text [
					all [none? size size: 15x5]

     make-gob/data compose/only [(xy) (size * metrics/cell) color (white) 
     text (text)] handler
				]
			]
			last-widget: last gob/pane
			;	1st reverse item?
			unless left-to-right? [

    last-widget/offset/x: last-widget/offset/x - last-widget/size/x
			]
			xy: last-widget/offset
			;	max vertical size
			max-y: max max-y xy/y + last-widget/size/y
			;	horizontal pos adjustments
			all [
				left-to-right?
				xy/x: xy/x + last-widget/size/x
				max-x: max max-x xy/x
			]
			;	after limit reached?
			either after-count < after-limit [
				;	spacing

    xy/x: xy/x + either left-to-right? [metrics/gap] [negate metrics/gap]
				++ after-count
			] [
				xy: as-pair metrics/margin max-y + metrics/gap
				after-count: 1
			]
			all [:word set :word last-widget]
			word: widget: action: handler: size: text: color: none
		]]


  parse reduce/only spec [after bar button handler return reverse rich 
  text] [
			any [
				opt [here: set arg paren! (here/1: do arg) :here] [
					'return (
						append-widget
						xy: as-pair metrics/margin max-y + metrics/gap
						left-to-right?: true
						after-limit: 9999
					)
					| 'reverse (
						append-widget
						xy: as-pair max-x max-y + metrics/gap
						left-to-right?: false
						after-limit: 9999
					)
					| 'after set arg integer! (
						;	return unless this is first widget
						if widget [
							append-widget
							xy: as-pair metrics/margin max-y + metrics/gap
						]
						after-count: 1
						after-limit: arg
					)
					| 'handler set arg block! (handler: arg)
					| 'rich set arg block! (text: arg)
					| [set arg integer! | set arg pair!] (size: arg)
					| set arg string! (text: arg)
					| [set arg tuple! | set arg none!] (color: arg)
					| set arg block! (action: arg)
					| set arg set-word! (append-widget word: :arg)
					| set arg word! (append-widget widget: arg)
				]
			]
		]

		append-widget
		gob/size: metrics/margin-size + as-pair max-x max-y
		gob/offset: system/view/metrics/work-size - gob/size / 2
		append system/view/screen-gob gob
		show system/view/screen-gob
	]]

	set 'undisplay make function! [[gob][
		remove find system/view/screen-gob gob
		show system/view/screen-gob
	]]

	;	Start global GUI event handler

	active-gob: none
	system/view/event-port: open [scheme: 'event]

 system/view/event-port/awake: make function! [[event /local evt gob][
		evt: map-event event
		gob: evt/gob
		while [not object? gob/data] [gob: gob/parent]
		if all [event/type = 'move gob <> active-gob] [
			attempt [active-gob/data/on-away event]
			active-gob: gob
			attempt [active-gob/data/on-over event]
		]
		evt: to word! ajoin ['on- event/type]
		attempt [gob/data/:evt event]
	]]
]

For example, the primary multitouch I miss in VID on OS X is 2-finger 
scroll, but it can be packaged as a scroll event, so should map. 
 (The issues we face will also be faced by all web browsers, so we're 
in good company.)

As I see it, you would want to map any facet in face 1 to any facet 
in face 2. Afterwards, you can judge whether that makes sense or 
not. This could be by checking for accepted datatypes in the target 
face at attach-time, but maybe that's too simple?


Also facet attachment should happen on as many faces as you need. 
If you want a slider to control 20 other faces with different facets 
as input and output, that should be possible. It's starting to look 
like a flow engine, so maybe we should take a look at what Maxim 
has done.

Something more to consider...

dynamic: group 1 [field field field] record [table1]


For when you want to set up fields where you know the order, and 
really want to minimize the layout code.


The outer panel would be set up with an ON-EMIT actor that traverses 
the inner faces. We already have this in the prototype, so maybe 
we can map the traverse order to the table columns.

OK, nice. And then, in draw block, I expect variables being used, 
which will map particular preselected material?

shaders must be very simple for speed. I'm not so terribly interested 
in actual realism, just a way to map a linear value to a specular 
value, which then gets tinted with a color.

Maybe we need two separate things - style grouping (use gui/widgets 
for that), and style hierarchy - tree or other map of styles, their 
inheritance and dependencies (maybe this is what Rebolek now referst 
to as an object browser?)

the functions map-inner and map-outer are not used anymore?

Ah... map-event is the old map-inner native function

I'm doing actually an API map for the R3-hostkit and this single 
page document is already much more instructive than any of what was 
done in 2010 ...!!!

we started to use multiple draw blocks?

 - they've been there for a good while now. :-) regarding naming, 
 I think it should reflect the specific state, rather than having 
 a "default". I usually prefer 'up, 'up-hover, 'down, etc. This is 
 easier to map to a state machine.

you should use a map when you don't like a block

I am still busy on my business trip, returning home tomorrow. I am 
thinking about producing Wiki article about what I find non optimal, 
or what I don't understand. So far I have gripes with 'options block, 
which does not map directly to facets, but is - artificial. That 
part has to move to declarative style definition, as it influences 
how you use the dialect ....

I think I understand the difference, but I was not easily able to 
see what is what, unless I studied it more deeply, and unless Ladislav 
told me during our meeting, that layout level 'options does not necessarily 
directly map to face/facets ....

Pekr, you said "layout level 'options does not necessarily directly 
map to face/facets"...that's why I don't want to rename OPTIONS to 
FACETS in the layout block. Also so far you are the only one who 
has problem understanding the 'options in layout vs. 'options in 
style definition and in fact you haven't proposed any concrete solution 
(evenin your CC ticket).

I'm not saying I'm against reasonable change here but since there 
is no good viable solution(and noone except you cares) we should 
 either wait until it pops out from someones head or just let it 
be as it is now.

This is part of Carl's original design and I imagine that he made 
the idea of "slots" as you call it, so there is a simple way to map 
grouped areas of code to faces, when they are created. Note in the 
source, the definition of a style and a face are right next to eachother. 
So it becomes "how do I create a face from a model of a face, as 
quickly and easily as possible?"

ARGS and PARAMS are ugly abbreviations of technical words. If the 
problem is that OPTIONS do not map directly to options in the face, 
it seems that WITH was the better name :-)

>> m: map [a: 42]
>> protect m
>> m/a
** Script error: protected value or series - cannot modify

Known bug? Not a bug, but a feature?

There are some real limits to op! evaluation that makes them unsafe 
for general use for now. For one thing, the type of the first argument 
is not checked at call time relative to the typespec by the evaluator 
- it has to be checked by the function itself internally. This is 
not a problem with most existing ops because they map to actions 
(which have their type compatibility handled by the action dispatcher), 
or in some cases natives that perform their own internal type checking. 
I believe this was a speeed tradeoff. If you allowed full user creation 
of ops even with their current restriction to actions and natives, 
you could bypass the typespecs of natives and corrupt R3's memory. 
Adding in that typespec check to the op! evaluator would slow down 
op! evaluation a little, but would be necessary if you really wanted 
to make user-defined ops possible.

Is a closure a function, where the vars is in a map (or whatever 
data structure is used for an object/context) instead of on the stack?

Thanks, Ladislav. Good examples!


The thing, I missed, was that REBOL has this extra internal data 
structure to hold symbols (words), I though, just the contexts was 
used for that. So comparing words (that are not bound to any context) 
are much faster than comparing strings in REBOL. I see different 
possibilities, depending on implementation. If a word is changed 
to the result from a hash calculation, then two different words might 
give the same result, right? It's unlikely, but it could happen. 
That's why map datastructures are combined with lists, when two different 
hash calculations give same result. The other possibility is, that 
words are changed to pointers pointing to their entry in the map 
(hash table). Do you know, what of the two, REBOL implement? In other 
words, could two different words be equal in REBOL?


About the strings, then it's possible to do kind of the same with 
hashing. Lua does that. If you have two different but identical strings 
(same string content) in Lua, they share the same memory area. Hashing 
is involved, and I guess, comparing string would be equal fast as 
comparing words, if REBOL did the same. (unless words are exchanged 
with the result from the hash calculation, but then two words might 
be equal)

The original was written before MAP-EACH and the new COLLECT. Here 
is the source I have, updated to use those as the current version 
does, but with the last rule reverted to the original.

Related cc reports: 
    http://issue.cc/r3/1096
    http://issue.cc/r3/690

split: func [

    "Split a series into pieces; fixed or variable size, fixed number, 
    or at delimiters"
    series	[series!] "The series to split"

    dlm		[block! integer! char! bitset! any-string!] "Split size, delimiter(s), 
    or rule(s)." 

    /into	"If dlm is an integer, split into n pieces, rather than pieces 
    of length n."
    /local size count mk1 mk2
][
    either all [block? dlm  parse dlm [some integer!]] [
            map-each len dlm [
                either positive? len [
                    copy/part series series: skip series len
                ] [
                    series: skip series negate len

                    ; return unset so that nothing is added to output
                    ()
                ]
            ]
    ][
        size: dlm   ; alias for readability
        collect [
            parse/all series case [
                all [integer? size into] [

                    if size < 1 [cause-error 'Script 'invalid-arg size]
                    count: size - 1
                    size: round/down divide length? series size
                    [

                        count [copy series size skip (keep/only series)]
                        copy series to end (keep/only series)
                    ]
                ]
                integer? dlm [

                    if size < 1 [cause-error 'Script 'invalid-arg size]

                    [any [copy series 1 size skip (keep/only series)]]
                ]

                'else [ ; = any [bitset? dlm  any-string? dlm  char? dlm]

                    [any [mk1: some [mk2: dlm break | skip] (keep copy/part mk1 mk2)]]
                ]
            ]
        ] 
    ]
]

split: func [

    "Split a series into pieces; fixed or variable size, fixed number, 
    or at delimiters"
    series	[series!] "The series to split"

    dlm		[block! integer! char! bitset! any-string!] "Split size, delimiter(s), 
    or rule(s)." 

    /into	"If dlm is an integer, split into n pieces, rather than pieces 
    of length n."

    /local size piece-size count mk1 mk2 res fill-val add-fill-val
][
    either all [block? dlm  parse dlm [some integer!]] [
        map-each len dlm [
            either positive? len [
                copy/part series series: skip series len
            ] [
                series: skip series len
                ; return unset so that nothing is added to output
                ()
            ]
        ]
    ][
        size: dlm   ; alias for readability
        res: collect [
            parse/all series case [
                all [integer? size  into] [

                    if size < 1 [cause-error 'Script 'invalid-arg size]
                    count: size - 1

                    piece-size: to integer! round/down divide length? series size
                    if zero? piece-size [piece-size: 1]
                    [

                        count [copy series piece-size skip (keep/only series)]
                        copy series to end (keep/only series)
                    ]
                ]
                integer? dlm [

                    if size < 1 [cause-error 'Script 'invalid-arg size]

                    [any [copy series 1 size skip (keep/only series)]]
                ]

                'else [ ; = any [bitset? dlm  any-string? dlm  char? dlm]

                    [any [mk1: some [mk2: dlm break | skip] (keep/only copy/part mk1 
                    mk2)]]
                ]
            ]
        ]

        ;-- Special processing, to handle cases where the spec'd more items 
        in

        ;   /into than the series contains (so we want to append empty items),

        ;   or where the dlm was a char/string/charset and it was the last 
        char

        ;   (so we want to append an empty field that the above rule misses).
        fill-val: does [copy either any-block? series [[]] [""]]
        add-fill-val: does [append/only res fill-val]
        case [
            all [integer? size  into] [

                ; If the result is too short, i.e., less items than 'size, add
                ; empty items to fill it to 'size.

                ; We loop here, because insert/dup doesn't copy the value inserted.
                if size > length? res [
                    loop (size - length? res) [add-fill-val]
                ]
            ]
            ; integer? dlm [
            ; ]

            'else [ ; = any [bitset? dlm  any-string? dlm  char? dlm]

                ; If the last thing in the series is a delimiter, there is an

                ; implied empty field after it, which we add here.
                case [
                    bitset? dlm [

                        ; ATTEMPT is here because LAST will return NONE for an 

                        ; empty series, and finding none in a bitest is not allowed.

                        if attempt [find dlm last series] [add-fill-val]
                    ]
                    char? dlm [
                        if dlm = last series [add-fill-val]
                    ]
                    string? dlm [
                        if all [
                            find series dlm
                            empty? find/last/tail series dlm
                        ] [add-fill-val]
                    ]
                ]
            ]
        ]
                
        res
    ]
]

split: func [

    "Split a series into pieces; fixed or variable size, fixed number, 
    or at delimiters"
    series	[series!] "The series to split"

    dlm		[block! integer! char! bitset! any-string!] "Split size, delimiter(s), 
    or rule(s)." 

    /into	"If dlm is an integer, split into n pieces, rather than pieces 
    of length n."

    /local size piece-size count mk1 mk2 res fill-val add-fill-val
][
    either all [block? dlm  parse dlm [some integer!]] [
        map-each len dlm [
            either positive? len [
                copy/part series series: skip series len
            ] [
                series: skip series negate len
                ; return unset so that nothing is added to output
                ()
            ]
        ]
    ][
        size: dlm   ; alias for readability
        res: collect [
            parse/all series case [
                all [integer? size  into] [

                    if size < 1 [cause-error 'Script 'invalid-arg size]
                    count: size - 1

                    piece-size: to integer! round/down divide length? series size
                    if zero? piece-size [piece-size: 1]
                    [

                        count [copy series piece-size skip (keep/only series)]
                        copy series to end (keep/only series)
                    ]
                ]
                integer? dlm [

                    if size < 1 [cause-error 'Script 'invalid-arg size]

                    [any [copy series 1 size skip (keep/only series)]]
                ]

                'else [ ; = any [bitset? dlm  any-string? dlm  char? dlm]

                    [any [mk1: some [mk2: dlm break | skip] (keep/only copy/part mk1 
                    mk2)]]
                ]
            ]
        ]

        ;-- Special processing, to handle cases where the spec'd more items 
        in

        ;   /into than the series contains (so we want to append empty items),

        ;   or where the dlm was a char/string/charset and it was the last 
        char

        ;   (so we want to append an empty field that the above rule misses).
        fill-val: does [copy either any-block? series [[]] [""]]
        add-fill-val: does [append/only res fill-val]
        case [
            all [integer? size  into] [

                ; If the result is too short, i.e., less items than 'size, add
                ; empty items to fill it to 'size.

                ; We loop here, because insert/dup doesn't copy the value inserted.
                if size > length? res [
                    loop (size - length? res) [add-fill-val]
                ]
            ]
            ; integer? dlm [
            ; ]

            'else [ ; = any [bitset? dlm  any-string? dlm  char? dlm]

                ; If the last thing in the series is a delimiter, there is an

                ; implied empty field after it, which we add here.
                case [
                    bitset? dlm [

                        ; ATTEMPT is here because LAST will return NONE for an 

                        ; empty series, and finding none in a bitest is not allowed.

                        if attempt [find dlm last series] [add-fill-val]
                    ]
                    char? dlm [
                        if dlm = last series [add-fill-val]
                    ]
                    string? dlm [
                        if all [
                            find series dlm
                            empty? find/last/tail series dlm
                        ] [add-fill-val]
                    ]
                ]
            ]
        ]
                
        res
    ]
]

Too bad we don't have a hierarchy of inequalities. Only two levels 
would be needed. Maybe a /case option to the functions that the the 
operators map to? Is it even possible to map an op! to a function 
that can take an option?

it allows you to hook up alternate graphics drawing within AGG or 
directly on the window which view opens.  though you still have to 
map all that nasty OS specific windowing event stuff first.  keep 
in mind that you might be able to do stuff like a datatype viewer 
right into the view engine  :-)

Would CTRL-C map to the EVT_INTERRUPT event?
I'm asking because when I do this:
>> wait system/view/event-port


R3 never returns and I cannot interrupt it. I'd like to fix this 
is possible.

The word "sufficient" there isn't quite true.  Explicit naming is 
more powerful... and provides a map as well from name to filename.

Even simpler:
>> map-each item [["xxx"] ["yyy"] ["zzz"]] [first item]
== ["xxx" "yyy" "zzz"]

heh .. not used map-each or collect before .. are these in R2 ?

EXTRACT works well for that, and maybe MAP-EACH too if you do nested 
blocks.

You might look at EXTRACT or MAP-EACH then. For simple queries with 
no joins, SQL is overrated.

>> map-each a [] [1]
** Throw Error: Return or exit not in function
** Where: map-each
** Near: return any [output make block! 0]

>> system/version
== 2.7.8.4.2

Here's a working version:

map-each: func [

 "Evaluates a block for each value(s) in a series and returns them 
 as a block."
	[throw catch]

 'word [word! block!] "Word or block of words to set each time (local)"
	data [block!] "The series to traverse"
	body [block!] "Block to evaluate each time"
	/into "Collect into a given series, rather than a new block"

 output [any-block! any-string!] "The series to output to" ; Not image!
	/local init len x
][
	; Shortcut return for empty data
	either empty? data [any [output make block! 0]] [
		; BIND/copy word and body
		word: either block? word [
			if empty? word [throw make error! [script invalid-arg []]]

   copy/deep word  ; /deep because word is rebound before errors checked
		] [reduce [word]]
		word: use word reduce [word]
		body: bind/copy body first word
		; Build init code
		init: none
		parse word [any [word! | x: set-word! (
			unless init [init: make block! 4]
			; Add [x: at data index] to init, and remove from word
			insert insert insert tail init first x [at data] index? x
			remove x
		) :x | x: skip (

   throw make error! reduce ['script 'expect-set [word! set-word!] type? 
   first x]
		)]]
		len: length? word ; Can be zero now (for advanced code tricks)
		; Create the output series if not specified
		unless into [output: make block! divide length? data max 1 len]
		; Process the data (which is not empty at this point)

  until [ ; Note: output: insert/only output needed for list! output
			set word data  do init

   unless unset? set/any 'x do body [output: insert/only output :x]
			tail? data: skip data len
		]
		; Return the output and clean up memory references
		also either into [output] [head output] (
			set [word data body output init x] none
		)
	]
]

I am making a simple (I hope) worfkflow prototype and want to use 
REBOL objects which I can SAVE and LOAD.  A workflow object!  to 
have a node-map collection in it of simple nodes of the workflow 
graph.   Source ->A -> B -> SINK where the workflow knows about the 
next node and status. Externally there is UI to support the work 
part ... which is URL data on a given node.   Looks like it fits 
into Cheyenne RSP well - maybe zmq when I get a bit further along. 
  Save a flow in process as a .txt file using SAVE/ALL filename.txt 
work-flow-instance.   But no success with work-flow-instance: LOAD 
filename.txt        Do I have to BIND on LOAD to re-instantiate the 
object?

probe load %/c/cheyenne/www/makework/data/wf001.txt
[make object! [
        id: 'wf001
        name: "Add Work"
        node-map: [make object! [
                id: 'SOURCE
                Description: "Add new software for Site"
                status: 'Complete
                Next-Node: 'A
                sub-tasks: "1. Used RFA to enter."
                When-completed: []
                Time: 60
                Notify: none
                status-url: func [] [

                    join http://localhost/makework/status.rsp?id=ID
                ]
                action-url: none
                mark-complete: func [] [
                    Status: 'Complete
                ]
            ] make object! [ ....

They stay as object! definitions viz  obj: do load %data/wf001.txt
>> probe obj
make object! [
    id: 'wf001
    name: "Add Software"
    node-map: [make object! [
            id: 'SOURCE
            Description: "Add new software for Site"

>> map-each e [] [e]
** Throw Error: Return or exit not in function
** Where: map-each
** Near: return any [output make block! 0]


is it a known bug? im new to cure code. i don't even know where to 
look for it. can some one help? (it works in r3)

CureCode: http://curecode.org/rebol3/view-tickets.rsp

Click on "Search" filter type, type "map-each" in input field, then 
hit [Find].

Onetom, that error has been reported already and fixed in R2/Forward, 
but it hasn't made it into R2 yet. Here is the revised MAP-EACH:

map-each: func [

 "Evaluates a block for each value(s) in a series and returns them 
 as a block."
	[throw catch]

 'word [word! block!] "Word or block of words to set each time (local)"
	data [block!] "The series to traverse"
	body [block!] "Block to evaluate each time"
	/into "Collect into a given series, rather than a new block"

 output [any-block! any-string!] "The series to output to" ; Not image!
	/local init len x
][
	; Shortcut return for empty data
	either empty? data [any [output make block! 0]] [
		; BIND/copy word and body
		word: either block? word [
			if empty? word [throw make error! [script invalid-arg []]]

   copy/deep word  ; /deep because word is rebound before errors checked
		] [reduce [word]]
		word: use word reduce [word]
		body: bind/copy body first word
		; Build init code
		init: none
		parse word [any [word! | x: set-word! (
			unless init [init: make block! 4]
			; Add [x: at data index] to init, and remove from word
			insert insert insert tail init first x [at data] index? x
			remove x
		) :x | x: skip (

   throw make error! reduce ['script 'expect-set [word! set-word!] type? 
   first x]
		)]]
		len: length? word ; Can be zero now (for advanced code tricks)
		; Create the output series if not specified
		unless into [output: make block! divide length? data max 1 len]
		; Process the data (which is not empty at this point)

  until [ ; Note: output: insert/only output needed for list! output
			set word data  do init

   unless unset? set/any 'x do body [output: insert/only output :x]
			tail? data: skip data len
		]
		; Return the output and clean up memory references
		also either into [output] [head output] (
			set [word data body output init x] none
		)
	]
]

Tonight's Moment of REBOL Zen:

Literal and Get Arguments in R2

see: http://www.rebol.com/docs/core23/rebolcore-9.html#section-3.2

These functions use Literal Arguments:


 ++ -- ? ?? cd default deflag-face first+ flag-face flag-face? for 
 forall foreach forskip help l ls map-each remove-each repeat secure 
 set-font set-para source

This function uses Get Argument:

	quote

It could be questioned, why functions like

	get set unset in catch throw checksum


, which all have arguments named WORD, don't use Literal Arguments?

Breakdown by reason:

- The word is pseudo-syntax for loop vars: FOR FORALL FOREACH FORSKIP 
MAP-EACH REMOVE-EACH REPEAT

- The function is pseudo-syntax for modifying operations on literal 
words as variables: ++ -- DEFAULT FIRST+

- Keyword arguments that aren't generally in expressions: DEFLAG-FACE 
FLAG-FACE FLAG-FACE? SECURE SET-FONT SET-PARA
- Interactive shell functions: CD LS ? ?? HELP SOURCE

Looks like SORT uses this datatype map internally:


[unset! datatype! native! action! function! object! word! set-word! 
get-word! lit-word! refinement! none! logic! integer! decimal! money! 
time! date! char! pair! event! tuple! bitset! string! issue! binary! 
file! email! url! tag! image! block! paren! path! get-path! set-path! 
lit-path! hash! list!]

>> source to-map
to-map: func [value][to hash! :value]

MAP-EACH under R3:
>> map-each v [] [v]
== []

MAP-EACH under R2:

>> map-each v [] [v]
** Throw Error: Return or exit not in function
** Where: map-each

the incorrect behavior won't necessarily cause a crash, but of course, 
it's probably not likely that map-each is used that way.

map-each: func [

 "Evaluates a block for each value(s) in a series and returns them 
 as a block."
	[throw catch]

 'word [word! block!] "Word or block of words to set each time (local)"
	data [block!] "The series to traverse"
	body [block!] "Block to evaluate each time"
	/into "Collect into a given series, rather than a new block"

 output [any-block! any-string!] "The series to output to" ; Not image!
	/local init len x
][
	; Shortcut return for empty data
	either empty? data [any [output make block! 0]] [
		; BIND/copy word and body
		word: either block? word [
			if empty? word [throw make error! [script invalid-arg []]]

   copy/deep word  ; /deep because word is rebound before errors checked
		] [reduce [word]]
		word: use word reduce [word]
		body: bind/copy body first word
		; Build init code
		init: none
		parse word [any [word! | x: set-word! (
			unless init [init: make block! 4]
			; Add [x: at data index] to init, and remove from word
			insert insert insert tail init first x [at data] index? x
			remove x
		) :x | x: skip (

   throw make error! reduce ['script 'expect-set [word! set-word!] type? 
   first x]
		)]]
		len: length? word ; Can be zero now (for advanced code tricks)
		; Create the output series if not specified
		unless into [output: make block! divide length? data max 1 len]
		; Process the data (which is not empty at this point)

  until [ ; Note: output: insert/only output needed for list! output
			set word data  do init

   unless unset? set/any 'x do body [output: insert/only output :x]
			tail? data: skip data len
		]
		; Return the output and clean up memory references
		also either into [output] [head output] (
			set [word data body output init x] none
		)
	]
]

R2's COLLECT is pretty similar. The backports try to be as compatible 
with R3 as is practical in R2, though is a couple cases they are 
a bit ahead of their R3 versions, where there are some tickets that 
haven't gone through yet. In particular ENLINE/with, DELINE block!, 
and MAP-EACH/into come to mind.

If you want to talk about intimidating R2 functions, look at APPLY 
or MAP-EACH. Neither of those would be accepted for R3.

I've noticed that FOREACH, FORALL and MAP-EACH are used the most.

It's not decimal precision which makes the FIND (and STRICT-MAP!) 
discussion so cumbersome.

Strangely enough, it's not binding or exact decimal comparison that 
are at issue with FIND or strict-map! either, it's case and type. 
Nonetheless, this would make it easier to point to the distinction 
between STRICT-EQUAL? and STRICT-EQUIV? when talking about those, 
precisely because those aren't at issue.

Ladislav, thanks. Seems the better option then would be to map == 
and !== to strict-equiv? and strict-not-equiv?.

I fear it is going to lead to problems if not all words are available 
to use in a context. Suppose there is an external source of data 
with named values that map naturally to a context. The ability to 
import that data easily will be broken if certain words are interpreted 
as hex values

Syllable maps the kernel into the first half of the address range. 
Programs are supposed to go into the upper half, but a Linux executable 
probably tries to map itself into Syllable's kernel area

We did a lot of research into the NDK for the R3 project. I was really 
interested in how an Android host program would be structured, how 
the Android application model would map to the R3 model. Hint: Android 
doesn't really have applications at all.

I have a basic binding with OSM GPS Map working

#include %OSM-GPS-Map.reds

gtk-view [
	gtk-maximize
	"OSM GPS Map Browser"
	osm-gps-map ogm-new-osd
]

The presentation of the map bindings at GeoFreedomDay went well - 
that is, after I could coerce my Linux to display on the beamer

http://red.esperconsultancy.nl/screenshots/OSM-GPS-Map-browser-on-RedSystem.png

http://red.esperconsultancy.nl/screenshots/Champlain-map-browser-on-RedSystem.png

I've published the map bindings here: