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World: r4wp

[Rebol School] REBOL School

Steeve
21-Apr-2012
[38x2]
>> blk: [greater? to-decimal do bind reduce [fact1] obj num1]
you"re doing tortuous things
Sujoy
21-Apr-2012
[40]
looks like it :(
Steeve
21-Apr-2012
[41]
So, Did you check my correction ?
Sujoy
21-Apr-2012
[42x4]
not working for me
>> foreach obj objs [print do blk]
** Script Error: Invalid path value: a
** Near: a/a
sorry!
>> foreach obj objs [print do bind blk 'obj]
** Script Error: Invalid path value: a
** Near: a/a
Steeve
21-Apr-2012
[46]
I repeat, did you take that correction ?
>> blk: [greater? to-decimal do bind reduce [fact1] obj num1]
Sujoy
21-Apr-2012
[47]
yes
Steeve
21-Apr-2012
[48x2]
It works fine with your data
copy that, it must work:

fact1: 'a/a
num1: 99.0
blk: [greater? to-decimal do bind reduce [fact1] obj num1]
objs: []
o: make object! [a: make object! [a: "100.0"]]
append objs o
o: make object! [a: make object! [a: "99.0"]]
append objs o
foreach obj objs [if equal?  do bind blk 'obj true [print obj/a]]
Sujoy
21-Apr-2012
[50]
bloody typo again. sorry steve. yes it does work. its 430am here...
Steeve
21-Apr-2012
[51x2]
Okay
Where are you from ?
Sujoy
21-Apr-2012
[53]
india
Steeve
21-Apr-2012
[54]
How have you discovered  Rebol, If I may ask ?
Sujoy
21-Apr-2012
[55x4]
online! was looking for something light and fast (in dev terms)
rebol is ideal
if i do:

fact1: 'a
o: make object [a: "100.9"]
append objs o
foreach obj objs [if equal?  do bind blk 'obj true [print obj/a]]
** Script Error: Invalid argument: a: "100.0"
wtf!
Steeve
21-Apr-2012
[59]
typo again
>> o: make object! [a: "100.9"]
you need sleeping time
Sujoy
21-Apr-2012
[60]
nope. i corrected that and still the same error.


i have data stored in json. i use json.r to convert to rebol objects. 
i want to create a query layer on top of this - which is why the 
expression builder...
the fact1 is an attr of the data object. these can be nested.
how best can i build the expression to retrieve the value i want?
Steeve
21-Apr-2012
[61]
There's no better response than: it can be done.
You just have to correct the bugs as they come.
Sujoy
21-Apr-2012
[62]
:)
Steeve
21-Apr-2012
[63]
is the complete error that one ?

** Script Error: Invalid argument: a: "100.0"

** Where: to-decimal
** Near: to decimal! :value
Sujoy
21-Apr-2012
[64]
yes
Steeve
21-Apr-2012
[65x2]
so you are trying to convert to a decimal something not convertible
add a probe, just after to-decimal
Sujoy
21-Apr-2012
[67]
hmmm...not that i know of...just using the test data i put in here:

>> probe objs
[make object! [
        a: make object! [
            a: "100.0"
        ]
    ] make object! [
        a: make object! [
            a: "99.0"
        ]
    ] make object! [
        a: "199.0"
    ]]
Steeve
21-Apr-2012
[68]
you are trying to convert an object to a decimal
Sujoy
21-Apr-2012
[69]
as long as fact1: 'a/a it works fine.
if fact1: 'a - boom!
Steeve
21-Apr-2012
[70]
because your objects have structures which are not always the same
Sujoy
21-Apr-2012
[71]
how do i tackle this?
Steeve
21-Apr-2012
[72]
what is the name of the decimal attribute ?
Sujoy
21-Apr-2012
[73]
a


blk: any [greater? to-decimal probe do bind reduce [fact1] obj num1 
| greater? to-decimal do bind obj/:fact1 obj num1]??
Steeve
21-Apr-2012
[74]
Currenlty 'a stands for either an object or a string, you can't be 
that vague.
You must choose a clear name  to identify the decimal attribute
Sujoy
21-Apr-2012
[75]
rats!
Steeve
21-Apr-2012
[76x3]
or you must check in your code when 'a is an object!
and fact1 must be initialized accodingly.
Either with 'a either with 'a/a
question:
an object 'a always has only one property called 'a ?
Sujoy
21-Apr-2012
[79]
yes
Steeve
21-Apr-2012
[80x3]
ok it's simpler then, let me try...
fact1: 'a
get-prop: func [o][either object? o [first next second o][o]]

blk: [greater? to-decimal get-prop do bind reduce [fact1] obj num1]objs: 
[]
another question. 

Why are you using the blk variable instead of coding directly in 
the foreach loop ?
The code would be simpler.
Sujoy
21-Apr-2012
[83]
meaning?
Steeve
21-Apr-2012
[84x4]
This is the same thing without the need of the blk code:

foreach obj objs [
	if num1 < get-prop obj/:fact1 [print obj/a]]
]
much simpler, no need to rebind anything
small mistake, missed the to-decimal.

foreach obj objs [
	if num1 < get-prop to-decimal obj/:fact1 [print obj/a]]
]
arghhh

foreach obj objs [
	if num1 < to-decimal get-prop obj/:fact1 [print obj/a]]
]