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I believe the PE file format has sections that are padded, so it 
may be that the internal padding is different, as are the code segments, 
but the resulting EXE is the same size. I suppose you could do a 
binary diff to see.

do the timers exist in the win2.7.4 build or only the osx build? 
 couldn't seem to find any relevant ? timer* info..

In new 2.7.4 build for OSX:
>> do http://www.rebol.com/speed.r
** Script Error: query has no value
** Where: halt-view
** Near: querying: to logic! query


Is networking turned off or something? It seems, I can't run any 
script over the net with this latest 2.7 build on OSX. It works with 
old REBOL/View 1.3.2 Core 2.6.3 build.

Cyphre, so if you can do anything to get text support in DRAW (under 
OSX and Linux??) and also push Carl to have prober event handling 
(something I haven't reported yet with the new Mac version), I'll 
really appreciate it. Maybe the time is now, where his hands are 
on View for OSX.

Do you know, if it's (or will be) possible to get struct! from handle!?

What if I expect float on the C side, but still want to allow to 
use integer from REBOL (using number!).. what's the best way to do 
it?

That's possible, but I was more thinking how to do it on the C side 
and not end with wrapper for each extension command.

I was trying to do just  (float)RXA_DEC64(frm, 1) with integer value 
and it was not working.

Do you think it's better to export all commands in flat structure 
like:
	export System_GetNumDrivers: command[]
	export System_GetDriverInfo: command[id [integer!]]
	...
Or rather close them to contexts like:
	export system: context [
		GetNumDrivers: command[]
		GetDriverInfo: command[id [integer!]]
		...
	]

For instance, in the AGG wrapper the commands that are used to implement 
the Draw dialect are exported in their own context rathar than globally, 
because they aren't meant to be called directly as functions. Other 
APIs may need to do the same thing for similar reasons.

Back to the name..  what if I export System extension context into 
main context, where is already System defined? Now it looks it just 
silently do not overwrites the existing one.. shouldn't it throw 
an error?

So do you want me to add CC ticket?

ok.. fine... so do you think I can safely use 'system' like exported 
names and believe, that if someone want's to use the extension, he 
will imported like:
	fmod: import %ext-fmod.dll
to avoid conflicts and not:
	import %ext-fmod.dll
?

Then please give them some more work to do

Maybe something to do with the length of the init block?

It's quite clear, what it should return, when you see it in REBOL 
like form, but it's quite difficult to do such a decision when parsing 
the spec.. that's also the main reason, why I decided to work on 
human readable dialect. (I was trying to generate the extension directly, 
it's possible, but it seems to be hard to maintain.)

I'm using this piece of code to get pointer to binary argument:
            char *srcData;
            REBSER *ser = RXA_SERIES(frm, 1);
            srcLen = - RL_GET_STRING(ser, 0, (void **) &srcData);
But also must do this:
	srcData+=RXA_INDEX(frm,1);

To fix the pointer to correct position if the source binary index 
is > 0.
Is this a bug or is it normal? Should it be reported in CC?

we should be able to do   arg.type directly.

Has it ever been discussed that R3 should be able to do IMPORT %file 
and know to look for %file.so on POSIX systems and %file.dll on Windows?

Earlier in the session of the call to the interpreter. When the program 
starts it loads the extensions and modules it needs. If you need 
to load things from specific filenames, do that before you load the 
other code. The module system is designed to help you organize and 
manage the code in a program.

You don't want IMPORT to do automatic lookup for more than one file 
extension because it's a potential security hole. For that matter, 
you should know if you're loading an extension instead of a module, 
because extensions could break the rules that REBOL source modules 
can't. And system/options/default-suffix can be set by your program. 
For that matter, the host code for LOAD-EXTENSION could translate 
.rx to .so on platforms that require .so and won't load .rx - that 
is a platform-specific restriction.

Do you have a problem with making an embedded delayed extension that 
loads cURL dynamically when the extension is imported? This is supposed 
to be possible, and is the main reason for delayed modules and extensions. 
Then only programs with Needs: [curl] would initialize curl.

R3 is cross-platform, and cURL is cross-platform, but both require 
a little work to make the platform distinctions go away. POSIX helps 
with this on POSIX platforms, but that's not everything. You can 
do a little extra work in your extension to make it work the same 
externally, so R3 code can't tell the difference, but if you want 
that to extend to filenames then you have to pick a cross-platform 
filename standard. Once the extension is loaded, embedded or delayed 
it can be referred to by module name. We don't want IMPORT to grab 
extensions in its module-paths lookup because that would make it 
possible to load an extension when you were looking for a safe module, 
so .rx and .so files aren't going to be in the search list unless 
your program sets system/options/default-suffix to .rx or .so, with 
the same security implications.

Do you have a problem with making an embedded delayed extension that 
loads cURL dynamically when the extension is imported? This is supposed 
to be possible, and is the main reason for delayed modules and extensions. 
Then only programs with Needs: [curl] would initialize curl.

LOAD-EXTENSION doesn't do lookup beyond the current directory, so 
if you want to have it use some library path you have to add that 
in the host code, or %rebol.r. Either way you can add extensions 
and modules programmatically to the R3 runtime before the script 
you're running starts. If you want your scripts to be cross-platform 
then you probably shouldn't use a platform-specific file extension 
for the files, but if they are loaded or delayed in the host code 
or %rebol.r then it wouldn't matter.

Alien binaries shouldn't be installed, so you need separate packages, 
or a package with an extension installer. If you really don't want 
to do that, you need subdirectories

Pekr, the idea behind .rx is to make it possible to write cross-platform 
extensions and have them be called by cross-platform code. If people 
are using extensions then they are expected to be importing them 
before they use them. The .rx convention is one way to do this; platform-specific 
loaders is another. Choose what you prefer.

Subdirs per platform is one way to do this (if you are calling your 
app from a network share, or building it from source for instance).

Oldes - maybe not, but those things have consequences. if we don't 
plan on collection resources info, how do we know how to free memory? 
That might influence some internals, modules, extensions, etc.?

Kaj, you do realize that you won't be able to just load any system 
library, right? Unless that library has an R3 extension API, it can't 
be loaded as an extension. And if you can only load R3 extensions 
anyways, why not name them as R3 extensions? The .so filename suffix 
isn't even portable to all POSIX platforms. If you want your code 
to be portable and load filenames, use a portable filename. That 
is why we have the .rx convention. And we have %rebol.r for anything 
specific to your personal platform - you don't even have to touch 
host code. For that matter, CGI scripts could call a R3 interpreter 
that is in a different directory than the user R3 interpreter so 
they would use different %rebol.r settings.

Oldes, Pekr, I don't know whether extensions can be unloaded. Last 
time I checked it was considered unsafe to do so, because the import 
process doesn't isolate things. In theory you could clean up after 
a module, remove it from the system modules list, remove all references 
to it from all other modules (that you have tracked), and then let 
the module be collected by the garbage collector, but I don't know 
if extensions are unloaded when they are collected.

I thought about user, downloading a distro. If those are not distinguished, 
I would try to DO each script, just to demo the REBOL. And doing 
a module usually does nothing more than loading the module = nothing 
visually usefull. So I would not mind having .r3, .rm, .rx

well, there was even one other suffix, for a compressed scripts, 
was it .rip? I like .r3, .rm, .rx, and those I will use (maybe really 
not necessary to do a separate suffix, I will see). .reb just says 
- nothing ...

we are very flexible, what do users think? I want free buttons, different 
extensions. I hope R4 prohibits user to load script, that would be 
best - we should be strict :-)))

But I want to do `import-extension 'zlib` and not:

import switch system/platform/1 [Linux [%zlib.so] Win32 [%zlib.dll] 
...]

I want to be able to setup a R3 config file that says:

extensions-dir:  %/some/path/


and then R3 will only ever load extensions from there.    the extensions 
can do whatever they want, but we have a controled point of entry 
within REBOL.

afaik, systems allow paths on dlopen.    rebol would simply always 
ask for libs with paths... 


in fact, on windows, that is how you are supposed to do it, probing 
the registry first to get proper paths for libs.

If you don't want your loader to look into the system paths for a 
specific app, tell it not to do so.

We do have a way to have extension search managed in a portable way 
by OS-specific means: LOAD-EXTENSION is implemented in the host code.

Yes, and all we need to do is add some simple filename management 
to it.

One interesting thing you haven't considered: sys/load-module calls 
lib/load-extension without checking whether it is native. You can 
override lib/load-extension with a REBOL code wrapper, in %rebol.r 
even. Then you can do any safe lookups you like without messing with 
host code, and even translate .rx suffixes to .so if you like.

All you have to do to use it, is to import the 'extload module first, 
before you import any native extension. After that, use the generic 
suffix to load extensions.


For example, let's assume you want to load your platform's cURL-binding.* 
extension:

import %extload.r3
import %cURL-binding.rx


On Linux (in the system/platform/1 sense) and FreeBSD, this will 
first attempt to load %cURL-binding.rx and if that fails, %cURL-binding.so.


On Windows, %cURL-binding.rx and %cURL-binding.dll are tried (in 
this order).


On OSX, %cURL-binding.rx, %cURL-binding.dylib and %cURL-binding.so 
are tried (in this order).

Do we need a system/options/extension-paths setting? You could add 
it to system/options in your %extload.r3, and it would let you preconfigure 
your system with a directory of shared extensions, if such a thing 
exists. Or it could just be assigned the same block as system/options/module-paths 
by default.

I built my own macros to do exactly this.  I proposed them to Carl, 
he mentioned he'd put them in the official distro... seems like I'll 
have to put them in git hub myself  :-)

The answer to that question is as yet unknown. Noone has tried it 
yet. Do you mean calling into the .NET APIs from native code, or 
calling into native code from .NET?

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?)?

cbi->obj is of type REBSER* so this suggest to pass in a series. 
A string with the name of the context?


Brian, how does a  "reference to the context containing the function" 
look for this:

rebol []

myfunct: does []

What do I pass to the extension here?

Those are the suggestions I would have, so I don't know what else 
to do

Thread synchronisation is also a complex topic. You can't just execute 
a piece of code in the context of another thread. The other thread 
has to execute it, and to make it do so you need a framework for 
that, such as a messaging infrastructure

Immediate values are copied. That's the first thing to do to reduce 
thread synchronisation problems

the real solution is to have R3 do this kind of thread synchronisation 
internally

Can someone explain me, why is Carl using such an 'encryption' and 
why not just to use it as const char like I do here:

https://github.com/Oldes/R3-extension-FMOD/blob/master/main.c#L417

Is it because he wants to be compatible with some old compilers?

Thanks! I've been using R2/Command to do the database access and 
R3 to process the data. All in the same script, using a trick I'll 
post to the Windows group.

Unfortunately, there's an error in its fallback behavior that makes 
it a bit difficult to use. In its docs, section 3.7:

 If there is no applicable REBOL datatype to contain a SQL value, 
 the value will be returned as a string.

The binary data is returned in a value of the string! type, rather 
than of the binary! type, which results in a corrupted string that 
you can't do anything with. If the value was returned as a binary 
then we could perform the conversions ourselves. I ran into this 
problem when returning SQL values of the tinyint and text types.

It'll be a while, before I'm available to do any skinning work.

I had mentioned earlier that it would crash due to complex layouts, 
but this is not the case. The layouts can be very simple. For example 
this one:

1. run graphical version of r3.exe

2. load following R3GUI release from web:

do http://www.rm-asset.com/code/downloads/files/r3-gui.r3

3. execute  this simple layout example:


view [tab-box ["tab1" [] "tab2" [] "tab3" [] "tab4" [] "tab5" []]]

There is definitely 'something' in the R3 Core that crashes the interpreter. 
At the moment it is very hard to track it without the access to the 
sources or having the debug release of the R3 library. (ie. I was 
able to trace the crash using the debug release of hostkit exe but 
the trace ended in the 'hidden' dll part so the hostkit code seems 
to be most probably out of the game here)

 IMO it has nothing to with the graphics part(unless there are 2 separate 
 bugs ;)) as I was able to crash R3 when writing non graphical script 
 as well. The crash is very hard to reproduce as it occurs only with 
 specific form of the executed script. If you change some line or 
 even order of words etc. the script works just fine.

It looks to me  either some GC or other memory allocation leak issue 
and have suspicion it have something to do with the map! datatype 
(but this is just my feeling).

I'm quite used to have several consoles opened which I use for multiple 
purposes and do not close them after each finished script. So I'm 
more affected by these possible GC bugs in R3.

The module system can be fixed to not use RESOLVE/extend/only, and 
a few months ago I submitted such a fix to Saphiron for them to include 
in their next host code release, along with other mezzanine fixes. 
I'm just waiting for them to post another release. In the meanwhile, 
in my own module code that does exports I do the exports explicitly 
in the module code itself instead of using the EXPORT keyword or 
the Exports header.

Hopefully this patch file will serve as an example for others who 
want to do similar patching.

I succesfully 'overloaded' some mezz functions in R3 in the RMA hostkit. 
See the inclusion of %rma-patches.r file in src\tools\make-host-init.r 
in the RMA host-kit release. So it is possible to do some fixes that 
way.(of course not every part can be tweaked such way)

I was using REBOL for datamining a few years ago and I can say it 
was easier to do string based parsing to get what I've needed.

It's always easier to do:  parse html [thru "<title>" copy title 
to "<"]  than parse complete html to something like a block structure 
and dig title in it.

For you, but my business partner wants to scrape web pages, and I 
don't think he would understand how to do it with parse

Again... it's easier to do manual changes to parse malformed pages 
if you do string parsing where you don't care about 99% of the page 
content.

I'm not going to do it for him, either, thank you very much

My approach was, instead of doing what many others do (try to remove 
things from the HTML that are known to be "bad", eg. use regexps 
to remove anything that starts with "javascript:" or anything between 
<script>...</script> etc.), was to only pass what was known to be 
good, and ignore everything else. This is a bit more limiting but 
I consider it to be safer (you don't have to play a game with attacker 
where every time they find a new vector, you have to add it to the 
"bad" list).

This method avoided keeping any intermediate representations in memory. 
However, because of that there were a number of things it could not 
do (eg. no look ahead, and you get an explosion of the number of 
states if you want to "look behind" more).

I was planing to use beaurtifullsoup if you didn't but since you 
do that is even much better

Rebol strings are stored either as ANSI (one byte) or wide char (double 
byte). Of course the rich-text module is currently doing the conversion 
for every rendered ANSI string in realtime. Any sophisticated rich-text 
caching is not yet implemented. (note: this has nothing to do with 
font glyph cache which works well) But even though the cache of large 
text block is missing the performance is still very usable for normal 
GUI cases so the priority to spend time on the line-cache is not 
too high at the moment.

I understand what Oldes wants. He want to be able to change already 
allocated Rebol string! from ANSI to WIDE-CHAR 'mode' so next time 
the conversion is not needed. Tha could be useful but has to be decided/implemented 
by Carl in the hostkit api.

Also it would be interesting to see how big is the difference between 
on-the-fly conversion performance to see if it really makes sense 
to permanently take two times more memory for such Rebol string or 
just do the temporary on-the fly conversion as it  works now.

It's possible to do such a test... just to compare the performance 
with ansi strings only and with strings which contains non ansi chars 
as well (so are stored as wide char internally). I can try it once 
I will have some time again.

I modified text-test3.r3 script from the host-kit to use normal sized 
font (12) not anti-aliased and used a little bit longer text content 
(but not extremely much. just two lines with length cca 1400 chars)... 
the result is:

Good news: I do not notice any difference between ansi/unicode content.

Bad news: in both cases R3 uses almost 23% of my CPU time when I 
just move mouse over the text, which is pretty much:/

Cyphre - what was the result of your acceleration experiment (not 
talking JITTer here)? I do remember it provided some further speed-up 
to some folks here (not to me on intel chipset). Will it  be added 
to hostkit by default, if it works under all Windows versions?

Has anyone tried compiling the hostkit for MinGW with the Cygwin 
compiler set? I'm trying to minimize the number of GCC installations 
on my Windows machine, and the Android NDK requires Cygwin to do 
its build process.

%rebol.r is run before any user code is run, even the --do and --import 
args. This makes it the best place to hack the module system for 
your own uses.

I would like to see some support for automatic logging of events.


Rebol currently has two "hooks" to allow "Front-end" code to execute 
automatically in the REBOL.r and USER.r files.

I would like to see another "hook" to allow "Back-end" code to execute 
automatically whenever Rebol stops its current evaluations for any 
reason such as encountering the HALT, QUIT, or any error which causes 
Rebol to stop evaluation.  


This could allow for some kind of automatic logging of  QUIT, HALT 
or ERROR as well as capturing the error messages.  It would be nice 
to allow capturing of any other information such as the script name, 
computer name, current timestamp, and where in the script the evaluation 
stopped, and how it stopped.


I would use this to log all of my scripts that is invoked (put the 
code in REBOL.r file) and then the termination conditions defined 
so they could be triggered automatically.  With such a function, 
I could even have certain selected scripts send an automatic SMS 
messages to my phone if certain scripts errored out etc.



I'd like to propose a new function called WHEN that can be used to 
trigger code at a terminating event.

WHEN  block  /all

For any specified terminating condition, evaluates what follows it.

Arguments:

block [block!] - Block of terminating events (conditions followed 
by values)
Refinements:

/all - Evaluate all terminating conditions (do not stop at first 
true terminating condition)


The WHEN command would be used to define code to be evaluated whenever 
a termination condition of any kind occurred in which continued evaluation 
will stop.

Examples:
WHEN/ALL [

 HALT?	[ print "This script will HALT now" ]  ; code to be evaluated 
 before the HALT is evaluated

 QUIT?	[ print "This script will QUIT now" ]   ; code to evaluate 
 befoe the QUIT is evaluated 

 ERR?	[ print "An error was discovered"  ]   ;code to evaluate after 
 an error is captured, but before the message is printed
	END?	[
		  print "Script about to end"
		  if  now/time  >  23:00:00  print "Stopped after 11 pm"

  ]                                                              ; 
   code to evaluate whenever the current evaluation has stopped for 
  any reason
	]


Note:  HALT?, QUIT?, ERR?, END? are all logic values which become 
true depending upon how evaluations will be stopped.

END? will always be true and one of the other terminating conditions 
will always be true.

What do you think?

Maxim <If an object has length, why can't I pick it?>
Maybe they are like SQL tables.....
A table has a length, so this is valid

   select count(*) from ....   -- to get the length of the table (ie 
   number of rows)

But, in the absence of an ORDER BY the rows do not have a user-accessible 
sequence, so

  select first from ....   -- is not valid syntax, nor (without an 
  ORDER BY) is it even meaningful

(Sorry, I know you did not want that debate)

btw the fact that pick can't use objects isn't related in any way 
to what length? can or cannot do.


I just gave an example to *illustrate* how clean it is to use thruty 
returns in real code.

whatever the algorithm or functions we use we will always have to 
handle the special cases (like 0 in maths)

yes, in such a sense (expensive change), I understand.  


I will wait for brian to step up and get his opinion.  I know we've 
spoken about this somewhat before, but not as head-on, for myself... 
 With the recent talk about naming, IMHO it has put a new light on 
the possibility for this to be a bit more appreciated, adding ? at 
the end would now mean something concrete.


let it be known that I do like errors, I am not against errors, I 
have been putting less and less error recovery in my code to make 
sure it crashes and I fix bugs early.


its just that I can see many if not most ****? functions (my own 
included) being truthy and this is very usefull to facilitate  control 
flow.  This, as oposed to always putting error handlers in places 
where the error is only used as a negative reply, for which we can 
supply, IMHO, a reasonable value/standard.

and clearly speaking about guru level stuff and not having a begining 
of a trail on such an issue makes me crazy just because noone wants 
to do this basic effort ...

maxim hum you know you do a splendid documentation full of stupidities 
to make Carl go on verbose mode and correct it that's what it's called 
preach the false to obtain the true :)

exactly when and how it works
 - there are at least two reasons why this is what you can't get:


1) *when* the GC works is "unpredictable" from the programmer's POV 
(depending on other code, etc.)

2) It is (or may be) subject to adjustments or changes, without the 
programmer being able to detect such changes, so why should he know?

3) programming for a specific GC variant should be seen as a typical 
bad practice - why should you want to make code that is supposed 
to work only in specific circumstances? Not to mention, that you 
actually cannot do that anyway, since the GC should be programmed 
to hide any implementation details

BrianH, if I deliver an application to a client and he says to my 
face... why does it jerk every 2 seconds?


I really don't care about if the GC might change.  right now I can't 
do anything to help it.


if it changes, I will adapt my code to it again.   This is platform 
tuning and it is inherently "close to the metal", but in the real 
life, such things are usefull to do... 

just look at the 1 second boot linux machine in that other group.

Actually, that feature might go away. The ALIAS function has been 
a big hassle in R3 because of the lack of a central system/words 
repository. We are likely to keep the aliasing facility for internal 
use to implement case insensitivity, but the ALIAS function to do 
other kinds of aliasing may go away.

Good to know. How would it affect numeric code if we made this change? 
Do we need operators for exact comparison?

prefix? and suffix? just return true if a series starts with the 
same items in the same order as the second one.  
the second argument is the prefix to compare

so you can easily do:

unless suffix? file-name %.png [append file-name %.png]

In the next release of glass, in the TO DO file, I list a few measurse 
to increase performance and decrease ram use by concentrating on 
using as much persistent data than throw away recycling.  but that 
means a complete overhaul of liquid and glob (the rendering engine 
over liquid).

maxim, do you plan to add more widgets to glass?

See http://issue.cc/r3/1573for remove-duplicates and the reason 
it's not as good an idea as you might think. It turns out that the 
set functions have to allocate a new series to do their work (for 
series larger than trivial size), even if they were changed to modify 
in place. So you can't avoid the allocation; might as well benefit 
from it.

It has to allocate another series anyways, as the set functions do 
hashing. In-place is just for convenience, not to save memory.

which is why its preferable to do it there anyways... and the fact 
that we only have one function name to remember for the two versions 
is also a big deal for simplicitie's sake.

I am pretty sure, that:


1) the set operations in Rebol are in fact GC-safe using the standard 
meaning of the sentence

2) it is always necessary to use auxiliary data, if the wish is to 
do the set operation efficiently

3) nobody pretending to need a modifying version really needs an 
inefficient variant, which does not use any auxiliary data

right now the GC is very cumbersome. it waits for it to have 3-5MB 
before working. and it can take a noticeable amount of time to do 
when there is a lot of ram.  I've had it freeze for a second in some 
apps.

everything we can do to prevent memory being scanned by the GC is 
a good thing.

right now the GC is very cumbersome. it waits for it to have 3-5MB 
before working. and it can take a noticeable amount of time to do 
when there is a lot of ram.  I've had it freeze for a second in some 
apps.

 - what exactly does the GC have in common with the "Deduplicate issue"?

even if done without aux data, it will still be MUCH faster to do 
in native.

I am curious who do you think would agree to write that nonsense

That is why I do not understand, why it is so hard to understand.

Every refinement with an optional value should accept also a none! 
(implied ?)
eg.
sum: func [
    "Return the sum of two numbers."
    arg1 [number!] "first number"
    arg2 [number!] "second number"
    /times "multiply the result"
    amount [number! none!] "how many times"
][	; test argument, NOT refinement
    either amount [arg1 + arg2 * amount][arg1 + arg2]
	; or if not amount [amount: 1] arg1 + arg2 * amount
	; or amount: any [amount 1] arg1 + arg2 * amount
]
so it would be possible to do:
summed: sum/times 1 2 (something) ;also if (something) is none

and obviously also:
summed: sum 1 2

instead of:
summed: either (something) [sum/time 1 2 (something)][sum 1 2]

Sorry but you are flying too high for me. I am tring to rewrite my 
sum function using aplly but do not understand how it could be done.

Btw, if there are other bugs in R3's PARSE that need to be discussed 
before being submitted to CureCode, this seems like a good group 
to do so.