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World: r3wp

[Core] Discuss core issues

Ladislav
14-Jul-2010
[17335x3]
In the DED (Data exchange dialect) none is a word, nobody wants to 
transform it to a value of a different type, and it actually never 
happens
...as Andreas demonstrated above, so why to pull out that strawman?
Generallly, "preprocessing REBOL scripts" means to work with the 
DED, not with the DD (Do dialect)
Maxim
14-Jul-2010
[17338x2]
but one must understand that when you LOAD data, no evaluation occurs, 
which is why serialization into litterals does not occur. 

this is a big detail, which most REBOLers do not grasp.


the litteral notation allows you to load items AS data, not as DO 
dialect source code.


I guess what could be done is to remove the /ALL refinement and add 
a new refinement which forces the non /serialized format.  but that 
makes SAVE work opposite of other serialization handling ... which 
is why I'm not sure that is such a good thing.
for data exchange, I really think that a deeper serialization is 
required.   even MOLD/ALL is inadequate for any serious project. 
 I've been bitten many times.  things like recursive object molding 
or breaking can occur.  ex:

>> a: context [b: none]
>> b: context [a: none]
>> b/a: a
>> a/b: b
>> mold/all a
{#[object! [
    b: #[object! [
        a: #[object! [...]
    ]]
]]}
Ladislav
14-Jul-2010
[17340]
but one must understand that when you LOAD data, no evaluation occurs, 
which is why serialization into litterals does not occur.
 - this looks like a confused statement to me. Example:

mold/all load "true" ; == "true"
mold/all load "#[true]"; == "#[true]"

There is no rocket science involved.
Maxim
14-Jul-2010
[17341x2]
in your first line... the loaded value is a word, not a #[true] value... 
but people don't get this.
it becomes obvious to advanced users, cause we've had to go deep 
into the bindology, but casual/intermediate REBOLers se all the datatype/binding/loading 
stuff as magic.
Ladislav
14-Jul-2010
[17343x2]
They should read http://en.wikipedia.org/wiki/REBOL#Syntax
This has nothing to do with any bindology, no rocket science involved
Andreas
14-Jul-2010
[17345]
even more of a reason why non-/all save needs to be abolished
Ladislav
14-Jul-2010
[17346]
exactly!
Maxim
14-Jul-2010
[17347]
I don't agree, SAVE & SAVE/ALL have different uses.
Ladislav
14-Jul-2010
[17348]
They do? Then, would you be so kind, and explain to me what is the 
purpose of SAVE? (I never found any)
Andreas
14-Jul-2010
[17349]
so what use do you have for non-/all save?
Maxim
14-Jul-2010
[17350]
well, the same for mold & mold/all


by all accounts, we should also abolish non-/ALL mold then, cause 
they are symmetric.
Andreas
14-Jul-2010
[17351]
(ok, i'll abstain. ladislav is faster :)
Ladislav
14-Jul-2010
[17352]
please, don't, have to run, bye
Maxim
14-Jul-2010
[17353x2]
I personnally NEVER use SAVE/ALL in any manner.   I always use WRITE 
so I can't even give you a valid case for SAVE/ALL  ;-)


but I've used SAVE a few times to log data.  Even when doing script 
pre-processing, SAVE/ALL broke too often for me to afford the hassle.


I'll usually use MOLD/ALL process the data as a string with real 
control then use WRITE
and even then, I don't LOAD scripts because we loose all the comments, 
so I pretty much always use LOAD/next, & string parsing to process 
REBOL source scripts.
Andreas
14-Jul-2010
[17355]
mentioning the perceived symmetry to mold and mold/all is kind of 
evading the argument. ladislav is arguing that SAVE should be useful 
with respect to LOAD. nothing stops us from defining SAVE as WRITE 
... MOLD/ALL ..., and there is no necessity to hold up this perceived 
symmetry.
Maxim
14-Jul-2010
[17356]
btw, I *am* playing devil's advocate here... ;-)


It might be that for the general purpose, SAVE/ALL might be the better 
default.  but IMHO SAVE itself is usually inadequate for storing 
DATA.  it might be ok for storing dialect blocks though.
BrianH
14-Jul-2010
[17357]
Ladislav, if you try to DO a script saved with SAVE/all or MOLD/all, 
it will fail if it contains functions or objects. And it definitely 
*won't* be "as close to original as possible". So /all can't be the 
default for SAVE.
Andreas
14-Jul-2010
[17358]
>> save/all %foo.r load/all "foo: func [x] [x * x] foo 42"
>> do %foo.r
Script: "Untitled" Version: none Date: none
== 1764

works pretty well!
BrianH
14-Jul-2010
[17359x2]
The primary purpose of SAVE is to save scripts that are to later 
be processed by DO.
Andreas, that isn't a function, it is a description of a function.
Andreas
14-Jul-2010
[17361x2]
It's a script, you said scripts
and that's the whole point. if you load a script and then save it, 
the original script should be affected as little as possible
BrianH
14-Jul-2010
[17363]
I also said functions and objects. That means function!, closure! 
and object! values, not their source.
Andreas
14-Jul-2010
[17364]
Yes, and that's the strawman. Those literal objects will only be 
written from a script if it contained them in the first place.
Ladislav
14-Jul-2010
[17365]
{And it definitely *won't* be "as close to original as possible".} 
- this is a Goebbels' truth, would there be any example?
Maxim
14-Jul-2010
[17366]
I gave one above.  if you try and save/all cross-referencing object! 
values the mold fails.
Ladislav
14-Jul-2010
[17367]
Yet another example of a Goebbels' truth:

>> do mold quote (1 + 2)
== 3
Maxim
14-Jul-2010
[17368]
in fact basic SAVE fails as well.
Ladislav
14-Jul-2010
[17369x2]
Max, you did not give any example, that would not deserve the "strawman 
prize", your DATA surely is not a DED
BTW, my above DO example demonstrates quite pregnantly, that DO isn't 
a "counterpart" of MOLD
Maxim
14-Jul-2010
[17371]
I don't get what you mean by strawman prize?
Andreas
14-Jul-2010
[17372]
maxim, you have a good point regardign serialising circular datastructures 
and similar stuff
Maxim
14-Jul-2010
[17373]
the objects could be within a block of data that you are trying to 
serialize... it would still fail.
Andreas
14-Jul-2010
[17374]
but it is a different issue than what we are discussing here
Ladislav
14-Jul-2010
[17375]
You built a strawman, since your example does not relate to the subject 
at all. The subject is: SAVE is not good to process DED.
Maxim
14-Jul-2010
[17376x3]
but SAVE is not only for DED, THAT is my point.
and in any case, you could have objects within your DED and SAVE 
would fail.
(*could* fail)
Ladislav
14-Jul-2010
[17379]
There is nothing that can be used to process non-DED and I agree 
with that, but that is a completely different subject
Andreas
14-Jul-2010
[17380]
no, you could not
Maxim
14-Jul-2010
[17381]
where is the DED defined?
Andreas
14-Jul-2010
[17382]
LOAD
Ladislav
14-Jul-2010
[17383x2]
Data Exchange Dialect, see http://en.wikipedia.org/wiki/REBOL#Syntax
, if you do not know what it is
{but SAVE is not only for DED, THAT is my point.} - that is not a 
point, that is a falsehood. SAVE is not even for DED (SAVE/ALL is), 
less so for non-DED data