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World: r3wp

[Core] Discuss core issues

Graham
25-Aug-2009
[14562]
I've tried various combinations of objects and blocks and usually 
the rebol-to-json function just breaks.
Maxim
27-Aug-2009
[14563]
I am beyond mystified!   what is wrong with this code?

(1.3 * (any  [rgb clr]))


both rgb and clr have tuple values... if I remove the any, it works, 
if I try the any and probe it, it returns the proper value... 

this is within a compose block.

 ** Script Error: Cannot use multiply on decimal! value
** Where: refresh-gfx
** Near: 1.3 * (any [rgb clr])
PeterWood
27-Aug-2009
[14564x2]
Try reversing the operands to the *. It seems to work:

>> clr: 0.0.0             
== 0.0.0
>> rgb: 4.4.4             
== 4.4.4
>> 1.3 * (any [rgb clr])  
** Script Error: Cannot use multiply on decimal! value
** Near: 1.3 * (any [rgb clr])
>> ((any [rgb clr]) * 1.3)
== 5.5.5
Haven't figured out why :-)
Maxim
27-Aug-2009
[14566x2]
I can almost swear I tried it!  but anyhow I did the 'ANY earlier 
in the code.... and just use rgb directly now...
thanks for the help though... this is a really strange bug :-)
Sunanda
27-Aug-2009
[14568]
R2 does not allow [decimal! * tuple!] but it does allow [tuple! * 
decimal!] with a tuple! as the result
    1.3 * 9.9.9
    ** Script Error: Cannot use multiply on decimal! value
    9.9.9 * 1.3
    == 11.11.11

R3 allows both, with a tuple! as a result.

Looks like an R2 bug fixed only in R3.
Graham
27-Aug-2009
[14569x3]
In forming iso-8601 dates , you need to add the sign of the time 
zone.

Would you believe that 

pick [ "+" "-" ] positive? now/zone

is 4x faster than this

either (1 = (sign? now/zone)) ["+"] ["-"]
It relies on the behaviour of pick using false is same as pick 2
Is that going to be the same in R3?
Sunanda
27-Aug-2009
[14572]
R3 looks the same as R2 in that respect, at least right now
    pick [ "a" "b" ] true
    == "a"
    pick [ "a" "b" ] false
    == "b"
Chris
27-Aug-2009
[14573]
pick "+-" positive? now/zone
Sunanda
27-Aug-2009
[14574]
Those three methods timed under R3:
    dt [loop 100000 [pick [ "+" "-" ] positive? now/zone]]
    == 0:00:00.511

    dt [loop 100000 [either (1 = (sign? now/zone)) ["+"] ["-"]]]
    == 0:00:00.504

    dt [loop 100000 [pick "+-" positive? now/zone]]

    == 0:00:00.35    ;; looks like the speediest under current alphas.
WuJian
27-Aug-2009
[14575]
If   time/zone is  0:00, should the answer be "-"?
Graham
27-Aug-2009
[14576x4]
I think it's normally + .. have to read up about it.  though + or 
- 0 is the same :)
In R2 quite different results


>> t1: now/precise loop 100000 [either (1 = (sign? -10:00)) ["+"] 
["-"]  ] difference now/precise t1
== 0:00:00.278

>> t1: now/precise loop 100000 [ pick [ "+" "-" ] positive? -10:00 
] difference now/precise t1
== 0:00:00.062

>> t1: now/precise loop 100000 [ pick "+-" positive? -10:00 ] difference 
now/precise t1
== 0:00:00.07
Interesting that R2 is much faster than F3 here.
R3
Sunanda
27-Aug-2009
[14580]
R3 is still beta -- so may be full of debugging code.

Also, are you comparing my times with yours? We have may have different 
speed machines
Henrik
27-Aug-2009
[14581]
fastest algorithms on R2 and R3 are generally equally fast here.
Graham
27-Aug-2009
[14582]
I should rephrase that .. interesting my PC is much faster than yours!
Sunanda
27-Aug-2009
[14583x2]
....Or not running as many other processes :)
Just tried your code on R2.  You do have a faster machine than me, 
and R3 is currently much slower for this benchmark:
== 0:00:00.39
== 0:00:00.046
== 0:00:00.047
Steeve
27-Aug-2009
[14585x6]
weird guys, but you don't do the same thing in R2 and R3 
(positive? -10:00) is 10 times faster than (positive? now/zone)
Another way (not faster but lol)

>>#"," - 1 == #"+"
>>#"," + 1 == #"-"

so, that should works like

>>#"," - sign? 10:00 

But it doesn't in R3, because

>> #"," - -1
==>> #"," - -1
** Script error: char! overflow/underflow
** Where: -
** Near: - -1
So, you can't add or substract a negative integer! to a char!, but 
you can add or substract a positive integer!
Weird, i said
Btw, with R2 it works

>> #"," + sign? -10:00
==#"-"
Seems a bug in R3
except, the formula was wrong
>> #"," - sign? -10:00
Sunanda
27-Aug-2009
[14591]
In R3, this will work:
    to-char (0 - sign? 10) + #","
    == #"+"
     to-char (0 - sign? -10) + #","
    == #"-"


Not quite as fast as Chris's suggestion, but rejigging to remove 
the (...) may help:
    dt [loop 100000 [to-char (0 - sign? -10) + #","]]
    == 0:00:00.39
Steeve
27-Aug-2009
[14592]
well, it's just a shame to have to reconvert to a char!
Graham
27-Aug-2009
[14593]
doesn't work with 0 for timezone
Steeve
27-Aug-2009
[14594]
ahah, yes
Graham
27-Aug-2009
[14595x3]
BY THE WAY,

pick "+-" negative? now/zone

fixes the 0 issue
-1 => "-" , and 0, +1 => "+"
sorry ... it should be  

pick "-+" negative? now/zone
Sunanda
28-Aug-2009
[14598]
Is my understanding of find/part wrong, or is this a bug?
     series: ["a" "b" "c" "d" "e"]
     find/part series "c" at series 3  

     == none      ;; fails to match using the [at series 3] part of  'series
    print mold at series 3  
    == ["c" "d" "e"]  ;; but [at series3] does contain the match
Dockimbel
28-Aug-2009
[14599x2]
The /part <range> argument (at series 3) is supposed to mark the 
end of the search range. So, here FIND is searching in ["a" "b"] 
only.
>> find/part series "c" 3
== ["c" "d" "e"]
>> find/part series "c" at series 3
== none
>> index? at series 3
== 3

This looks like an inconsistency to me.
Steeve
28-Aug-2009
[14601]
what do you mean Doc ? It has been always like that.

with /part you can specify a length or a terminal pointer to the 
serie.
What's wrong with that ?
Maxim
28-Aug-2009
[14602]
/part makes the compare a record.  so its expecting a block to match 
I think.
Steeve
28-Aug-2009
[14603]
? find
        /part -- Limits the search to a given length or position
                length (number! series! pair!)

It seems clear to me
Dockimbel
28-Aug-2009
[14604]
/part -- Limits the search to a given length or position
, you're right, I've missed the "length or" part..
Steeve
28-Aug-2009
[14605]
it should say "tail position" to be exact
Maxim
28-Aug-2009
[14606]
doh.... sorry... my mind mixed-up /part with /skip...
Sunanda
28-Aug-2009
[14607]
Thanks. What was confusing me is an inconsistency between R2 and 
R3 -- was not sure if R3 was the bug fix or the problem.
R2:
    select/part series "c" at series 4
    == "d"
R3: 
    >> select/part series "c" at series 4
     == none

*** Do we agree R3 is right in this case?
Steeve
28-Aug-2009
[14608x2]
yep
i use /part a lot, for example when i want to to find something in 
the first line of a text.
>> find/part text "something" any [find text newline tail text]
Sunanda
28-Aug-2009
[14610]
Looks like its a RAMBO report then, rather than curecode :)
james_nak
28-Aug-2009
[14611]
Bind. I often use blocks of field (column) names from a db table 
in functions. Trouble is when I add a field I have to go back and 
add that field name to every place where I am using my fields.  I 
was thinking of just creating a block at the beginning of my code 
and then using "bind" to create a local context. I just can't seem 
to make it local. It behaves as a global. Is there some trick?