r3wp [groups: 83 posts: 189283]
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World: r3wp

[!REBOL3-OLD1]

Henrik
11-Apr-2006
[363]
very
Graham
11-Apr-2006
[364]
whatever result is returned by an operation on the block can also 
be an element in that block.
Henrik
11-Apr-2006
[365]
yeah, what if your block contains an error! object?
Graham
11-Apr-2006
[366]
exactly.
Henrik
11-Apr-2006
[367x3]
but then the problem exists in FIND to for example
which returns none on not found, but there we have the FOUND? to 
help us. perhaps the ordinals should use FOUND? as an indicator?
found? second [true none]
Graham
11-Apr-2006
[370]
found? is just not none
Henrik
11-Apr-2006
[371]
I thought it was smarter than that, but maybe it could be smarter 
in 3.0
Graham
11-Apr-2006
[372]
>> source found?
found?: func [
    "Returns TRUE if value is not NONE."
    value
][
    not none? :value
]
Henrik
11-Apr-2006
[373]
oh :-)
Pekr
11-Apr-2006
[374]
:-)
Graham
11-Apr-2006
[375]
I use it as a shortcut for not none?
Henrik
11-Apr-2006
[376]
well, it would also eliminate the performance advantage that ordinals 
apparently give
Pekr
11-Apr-2006
[377]
then we need some flag to be settable for none? strict? none? blk/3
Graham
11-Apr-2006
[378x2]
Perhaps we need a way to configure the behaviour we want?
if your data doesn't have none, then you can accept none for a range 
error.
Pekr
11-Apr-2006
[380]
I thought about it too :-) e.g. copy-by-default: true, etc. :-)
Graham
11-Apr-2006
[381x2]
I suspect it was a mistake to allow an out of range to return none.
Too late now though ..
Geomol
11-Apr-2006
[383x5]
Regarding pair and decimals; would it make sense to generalize pair 
further into a new vector datatype, that can be any dimension more 
than one? Examples: 2.4x8.0x5.5 would be a 3D vector with coords 
(2.4; 8.0; 5.5). Like the same idea with tuples, which can be 3 or 
more bytes separated by dots: 255.255.255, 255.255.255.255,... etc.
Or should that be handles with user-defined datatypes?
*handled*
And going further, if we take the vector road, what about matrices?
Support for multi-dimensional vectors and matrices in rebcode might 
lead to something really interesting. ;-)
Graham
11-Apr-2006
[388x2]
I think it should be handled natively
but it could get ugly quickly.
Geomol
11-Apr-2006
[390x3]
The alternative, doing vector- and matrix-math just using decimals, 
can easily be ever uglier.
Imagine having a matrix! datatype:
m: make matrix! 4x4
Then you could find the determinant like for example:
m/determinant
That would be a miracle! :-)
Suddently complicated math can be made very simple.
Henrik
11-Apr-2006
[393]
it would also be a miracle to be able to have a complex! datatype. 
I think electronic engineers would appreciate that
Graham
11-Apr-2006
[394]
How to submit a suggestion to Carl?
Pekr
11-Apr-2006
[395]
feedback or comment on blog?
Henrik
11-Apr-2006
[396x3]
or rambo?
geomol, I once had the idea that you could define ISO units as kind 
of datatypes and do scientific calculations on them
my calculator can do that, so why not have it in rebol?
Geomol
11-Apr-2006
[399]
Henrik, give an example!
Graham
11-Apr-2006
[400]
Geomol, Rambo the suggestion for a vector datatype.
Rebolek
11-Apr-2006
[401]
and what about interval computations? :)
Graham
11-Apr-2006
[402]
Let's stick with 3 dimensions.
Henrik
11-Apr-2006
[403x2]
well, I'm really not sure about the notation as I haven't given it 
too much thought, so I can't give a valid example, but if you could 
say:

>> 6 / 2
== 3

>> 6 [m] / 2 [cm]
== 300 [cm]
this is no good, but some method to attach units to numbers and variables 
and make REBOL aware of them during calculations
Graham
11-Apr-2006
[405]
>> $5.00 / 20
== $0.25
Geomol
11-Apr-2006
[406]
Henrik, ah ok. Yes, good idea!
Graham
11-Apr-2006
[407]
so we can do mixed imperial and si calculations ??
Geomol
11-Apr-2006
[408]
Something like:
ISOm6 / ISOcm2
Henrik
11-Apr-2006
[409x3]
sure, my HP48 can do that easily
as long there is some definable way to convert between them or make 
some sense from it
the acceleration of gravity would be 9.82 [m/s/s] so units themselves 
are math expressions
PeterWood
11-Apr-2006
[412]
It that something for a dialect rather then to be inlcuded in the 
core langauge?