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[Core] Discuss core issues

TomBon
19-Feb-2009
[12447]
cool
[unknown: 5]
19-Feb-2009
[12448x2]
TomBon, keep in mind that you can create the spec for an object and 
use it as your template as well.
>> blk: [a: 1 b: 2]
== [a: 1 b: 2]
>> obj: context blk
>> obj/a
== 1
>> obj/b
== 2
Graham
19-Feb-2009
[12450]
If you look at the source for 'function, you will see that the parameters 
are just 2 blocks ....
TomBon
19-Feb-2009
[12451]
yes but the objects also containing functions and nested objects 
etc. graham approach is very compatible with the current codebase 
I have so far but thx for reminding me with this paul.
[unknown: 5]
19-Feb-2009
[12452]
Your welcome TomBon, glad to see that you got the problem resolved.
[unknown: 5]
21-Feb-2009
[12453]
What part of this is a bug:

>> val: 'blah
== blah
>> type? val
== word!
>> lit-word? val
== false
>> help val
VAL is a word of value: blah
>> val: to-lit-word val
== 'blah
>> type? val
== word!
>> lit-word? val
== false
>> help val
VAL is a lit-word of value: 'blah
Anton
21-Feb-2009
[12454]
Lit-words reduce to words pretty easily, so try this instead:
	type? :val
[unknown: 5]
21-Feb-2009
[12455x4]
Yeah I actually realized that after I posted it.
What was confusing me is assignment and how it works with lit-word
Consider the following:

>> a: 'test
== test
>> lit-word? :a
== false
>> a: to-lit-word 'test
== 'test
>> lit-word? :a
== true
Seems to me that the assignment aspect is still buggy.  i would expect 
to get lit-word? true on the first call in that example.
Izkata
21-Feb-2009
[12459]
The way I see it:

In your second post,

'test is a lit-word! being evaulated to a word! before assignment 
to 'a, in the first part

In the second part, the lit-word! 'test is being evaluated to a word!, 
passed into the function to-lit-word, then the lit-word is assigned 
to 'a


In the first post, why "type? val" returns word! on a lit-word!, 
I see as the same as this - the type is a subset:
>> X: %One
== %One
>> type? X
== file!
>> series? X
== true
[unknown: 5]
21-Feb-2009
[12460x2]
It just seems inconsistent to me but I suppose it is needed to be 
this way to deal with the manner in which REBOL operates.  For example, 
consider its inconsistency in this regard:

>> string? "this"
== true
>> file? %file
== true
>> lit-word? 'this
== false
Also consider this:

>> a: first ['test]
== 'test
>> lit-word? :a
== true
>>
Izkata
21-Feb-2009
[12462]
It's always felt consistent to me - the context is being evaluated, 
and lit-word!s reduce to word!s, word!s reduce to functions and values, 
while other datatypes reduce to themselves:
>> X: [{One} 'Two]
== ["One" 'Two]
>> ? X/1 ? X/2
X/1 is a string of value: "One"
X/2 is a lit-word of value: 'Two

>> X: reduce X   ;Here is where typing it in on the terminal evaluates 
to
== ["One" Two]
>> ? X/1 ? X/2
X/1 is a string of value: "One"
X/2 is a word of value: Two
>> X: reduce X
** Script Error: Two has no value
** Near: Two

...and the reasoning behind lit-word!/word! acting differently is 
that those are special datatypes where other values can be bound 
to them
[unknown: 5]
21-Feb-2009
[12463x2]
My point is that I don't see why the to-lit-word isn't implied when 
performing assignment.  Such as a: 'test
BTW, it is more efficient to assign a lit-word with a: first ['test] 
then it is to use a: to-lit-word 'test.
Janko
21-Feb-2009
[12465x3]
(I participatted in this discussion already one time and it also 
seems consistent to me)
Paul: I think Brian or Henrik told that time that 'word is "active" 
something and rebol reduces it when encounters it in the same way 
as it would auto-reduce function a: get-two not assign it to a (at 
least that was my compilation of it that time :) )
and we all know that blocs don't get evaluated / reduced by itself 
so [ word ]  stays [ word ] even fi word is undefined or func or 
anything so [ 'word ] also stays [ 'word ]
[unknown: 5]
21-Feb-2009
[12468x2]
That makes no sense to me Janko.  By the way it was me and Henrik 
that both thought it was inconsistent.
Janko, this seems consistent to you:

>> lit-word? 'test
== false
Janko
21-Feb-2009
[12470]
it maybe seems odd at first sight, but consistent in the same way 
as this:

>> make-two: does [ 2 ]
>> make-two
== 2
>> function? make-two
== false
Rebolek
21-Feb-2009
[12471]
Paul, it is consinstent:

read first word - it's >lit-word?<
evaluate it - it's a function that takes one argument

read second word (first and only argument for that function) - it's 
>'test<
evaluate it - lit-word! evaulates to word!
pass it to the function - word! is passed, not lit-word!
[unknown: 5]
21-Feb-2009
[12472]
Ok, if everyone else thinks so then this is one of those issues where 
its only me that thinks it isn't.  As long as newbies GET IT when 
learning REBOL that is what matters.
Janko
21-Feb-2009
[12473x2]
I am not so exp. rebol user as you but where do you use lit words 
as they are.. I used them only to pass words (reduced lit-words) 
basically so far ... in blocks never

 write  [  'some 'random 'words ]  but  [ some random words ]  as 
 they don't get evaled anyway
Paul: maybe you have a different usage pattern for them, so this 
behaviour that goes on looks odd/wrong when used that way?
[unknown: 5]
21-Feb-2009
[12475x4]
yes Janko but that can be risking if they do get evaluated.  consider 
this [delete %/c/bootmgr]
See I read the documentation on lit-word? and it states:

Returns TRUE for lit-word values.
But you guys tell me that 'test is not a lit-word value.
That is what doesn't make sense to me.
Janko
21-Feb-2009
[12479x2]
yes, I get this delete example :) good point ,... I would have to 
look in what manner I used blocks with "random" words (if I did) 
to see what could happen..  I did some when I was playing with dialects.. 
and to store data in [ key "value" ]  manner
is make-two a function ? it is but when you write it it gets evaled 
to 2 and if you write >>function? make-two<< you get false , same 
here it is but it get's evaled to word
[unknown: 5]
21-Feb-2009
[12481x2]
But 'test is a value - not a function.  It is the end value as I 
call it.  In other words it doesn't evaluate.
words can evalute but lit words don't.
Rebolek
21-Feb-2009
[12483]
no, lit words evaluate to words
[unknown: 5]
21-Feb-2009
[12484x4]
I know it does which is why I believe that is inconsistent.
I currently get this:

type? 'test
==word!

I think it would be more consistent to get this:

type? 'test
==lit-word!
Consider this link by Brett:

http://www.codeconscious.com/rebol/articles/rebol-concepts.html

It says the following:

'age

This textual form is recognised in rebol as the lit-word! datatype.
See that isn't entirely true - only half true.  Consider:

>> lit-word? 'age
== false
Rebolek
21-Feb-2009
[12488]
But this is purpose of lit-word! With your behaviour,
>> reduce ['a] ; would return
== ['a]
[unknown: 5]
21-Feb-2009
[12489x3]
But that makes sense to me.
That is why I say that it is only half true to say that it evaluates 
to a lit-word.
It does sometimes but not all the time.
Rebolek
21-Feb-2009
[12492x2]
No, it evaluates to word!, not lit-word!
Always
[unknown: 5]
21-Feb-2009
[12494]
To me that is the inconsistency.
Rebolek
21-Feb-2009
[12495]
Paul, with your behaviour, how would you write this code?:

>> a: 3
== 3
>> reduce ['a a]
== [a 3]
[unknown: 5]
21-Feb-2009
[12496]
to me it should be ['a 3]