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World: r3wp

[!REBOL3]

BrianH
16-Mar-2010
[1587]
Right. That was fixed in R3 recently.
Gregg
16-Mar-2010
[1588]
Cool. Thanks.
BrianH
16-Mar-2010
[1589x4]
Just to make it clear: The behavior you describe in R3 was the result 
of the fix :)
bug#1443 to be specific.
Though for file! literals it was like that before, afaik. #1443 extended 
that to email! and url! literals.
I understand your take on Carl's proposal for a change in RETURN 
and EXIT scoping, but it needs some work before it can do the job. 
For one thing, if you have dynamic as an option (or a default) there 
is still the need for something like R2's [throw] attribute. And 
if definitional is an option, not the default, then I'm having a 
lot of trouble justifying that option, especially since it doesn't 
solve the [throw] issue or bug#1506. It seems to me that the main 
reason for definitional is to make a simpler default for less advanced 
developers. If it's an option that the user has to chose, it doesn't 
serve that purpose. And if it's an option that gets conflated with 
the option to specify a typespec for the return value of the function, 
then this is going to get Fork furious about making REBOL more confusing, 
and he'll be right this time.
Ladislav
16-Mar-2010
[1593x2]
how about this, is it intended?
>> f:  func [self] [self]
** Script error: duplicate variable specified: self
** Where: make func
** Near: make function! copy/deep reduce [spec body]
(that looks like illustrating your note, that 'self is a keyword)
BrianH
16-Mar-2010
[1595x2]
Nope, it is not intended, it is a bug. Report it.
Only closures and FUNCT/with should define 'self; regular functions 
shouldn't.
Ladislav
16-Mar-2010
[1597x2]
Why closures, is it of advantage for closures?
(I do not see it as an advantage, maybe overlooking something...)
BrianH
16-Mar-2010
[1599]
The contexts of closures persist outside of the scope of their execution, 
like objects. The contexts of functions don't.
Ladislav
16-Mar-2010
[1600x2]
yes, I know that, but does it need to use 'self because of that?
(my closures originally did not use 'self)
BrianH
16-Mar-2010
[1602]
Not unless the closure has no arguments, but it doesn't hurt enough 
to get rid of it. On the other hand, we should probably get rid of 
'self binding from FOR, REPEAT, FOREACH, MAP-EACH and REMOVE-EACH 
(it's already been reported).
Ladislav
16-Mar-2010
[1603]
yes, that looks inappropriate
BrianH
16-Mar-2010
[1604x2]
I would be willing to accept getting rid of 'self binding from closures 
if that is the choice, no big deal.
The 'self bound by FUNCT/with is bound to the object context, so 
it should stay.
Ladislav
16-Mar-2010
[1606]
'self binding from FOR,
 could you point me to the ticket?
BrianH
16-Mar-2010
[1607]
Weird, can't find it. I remember someone reporting it - must have 
been in chat. Report it.
Ladislav
16-Mar-2010
[1608]
OK
BrianH
16-Mar-2010
[1609]
I would myself but don't have the time today (friend in hospital). 
I can refine any tickets later if you like.
Ladislav
16-Mar-2010
[1610]
OK, no problem
BrianH
16-Mar-2010
[1611]
It seems that functions don't bind 'self to the code block, but they 
do reserve it in the function spec. So that's a separate ticket.
Ladislav
16-Mar-2010
[1612]
yes
BrianH
16-Mar-2010
[1613x3]
And closures don't bind 'self anymore either (I now vaguely remember 
a ticket related to that).
Note: The duplicate variable 'self bug in function and closure specs 
might be dismissed (not by me). It could be necessary for the implementation 
to have an internal 'self in the function contexts; only Carl could 
say for sure.
That seems like more of a gotcha than a bug though.
Ladislav
16-Mar-2010
[1616x3]
>> g: func [] [self]

>> same? 'self first body-of :g
== false
hmm, seems to be used
how about the #447, it does not look like accepted to me?
BrianH
16-Mar-2010
[1619]
It's not rebound by the function. What you are seeing is the script 
context.
Ladislav
16-Mar-2010
[1620]
>> a: 'self
== self

>> b: 'self
== self

>> same? a b
== true
BrianH
16-Mar-2010
[1621x3]
Right. Scripts all use the same default context: system/contexts/user.
Modules get their own contexts.
>> same? self system/contexts/user
== true
Ladislav
16-Mar-2010
[1624]
then, what makes the difference in the above case of the function 
body?
BrianH
16-Mar-2010
[1625x2]
The 'self word you are comparing is not bound to the function context, 
it is bound to the script context.
Or whatever other "outer" context 'self is bound to depending on 
where the function was defined.
Ladislav
16-Mar-2010
[1627x2]
>> a-body: [self]
== [self]

>> g: func [] a-body
>> same? first a-body first body-of :g
== false
so, something has to happen when the Func is called
BrianH
16-Mar-2010
[1629]
No, something happens in BODY-OF - the words are unbound in the copy 
of the body returned, for security purposes.
Ladislav
16-Mar-2010
[1630x2]
right, sorry
>> a-body: [first [self]]
== [first [self]]

>> g: func [] a-body
>> same? first second a-body g
== true
BrianH
16-Mar-2010
[1632]
>> a-body: [self same? first a-body 'self]
== [self same? first a-body 'self]
>> g: func [] a-body
>> g
== true
Ladislav
16-Mar-2010
[1633]
and how about #447, do you consider it solved?
BrianH
16-Mar-2010
[1634]
Yeah. It must have been reported by that other BrianH :)
Ladislav
16-Mar-2010
[1635x2]
which one?
LOL