World: r3wp

Sorry, I wanted to type Volker, of course!

; Q1: copy/deep will give you new strings:
block: [none none none]
new-block: copy/deep replace/all block 'none {}

; Q1 Or if you know you can reduce it you could do something obtuse 
like:
block: ["a" none "b" none none]
use [none][none: does [copy {}] bind block 'none]
reduce block

But if you do need to do an actual replace on the original block 
- see the other solutions :-)

Hi Brett, your first version looks pretty good ... now I'll have 
to dig out my little profiler, and see what's the fastest of all 
of these ;-)

I reckon the parse will win.

Brett's is the nicest looking though.

Brett, your obtuse way will only work if you are replacing 'none 
(as a word), but not none! values.

eg. reduce your input block:
	block: reduce ["a" none "b" none none]

Agreed Anton and perhaps that shows the obtuse method is not a great 
idea for this situation  - though perhaps an interesting one ;-)

In case anyone is interested... http://www.rebol.org/cgi-bin/cgiwrap/rebol/view-script.r?script=reboldiff.r

Are there any other instances where the a: copy [] vs. a: [] "problem" 
appears?

I'm have a bug where two arrays:

1. an array with data that can be manipulated

2. a similar one containing default data, which is used whenever 
I want to reset the first one


They apparently "stick" together with synchronized values. When I 
manipulate array 1, array 2 changes too. This would be the old COPY 
problem, but I use COPY everywhere, whenever I need to create array 
2.


However I do frequently PICK values from array 2 and POKE it in array 
1 at the same location to reset a specific location to a default 
value. Would that create a similar problem?

it depends on the kind of value you are picking/poking.

i guess you need copy/deep and poke ... copy pick ...

I pick and poke arrays

i mean, what is the result of PICK? i.e. what is inside the arrays?

if the arrays have multiple dimensions, you need copy/deep. And if 
there are objects inside, those objects are not copied, then you 
need explicit work (copying all objects in a loop using 'make)

Volker, the arrays are indeed both 2 dimensional and contain objects. 
I'll try a different init method.

gabriele, the arrays contain other arrays, hence PICK returns arrays 
of objects.

so, copy/deep, and, as volker suggests, you're likely to need to 
clone the objects too.

thanks, both. problem solved. :-)

a one liner I didn't see on rebol.com: Sum of all numbers in a block!:

do do replace/all mold [1 2 3 4 5] " " " + "

Clever!
But crucially dependent on the block being contained on one line:
 xx: {
 do do replace/all mold [1 2 3
  4 5] " " " + "
 }
 do xx

But then you did call it a one-liner :-)

do trim/lines xx could fix that

Is there a function which cuts the suffix, so i can go from %file.txt 
to %file.html ? I  remember darkly there is one now.

I think there is one which splits a file up in an object with path, 
filename and extension. can't remember which though....

thats decode-url, good thought, but not in my case.

what about cutting at last occurance of "dot"?

longer :) but thats what i do now.

>> prefix: func [filename][copy/part file find/last file "."]
>> prefix file
== %movie.cd1.divx-rel6

where - >> file: %movie.cd1.divx-rel6.avi

maybe 'prefix? would be good addition to Core, as we have 'suffix? 
already? :-)

thats cool, better than mine :) thanks.

but prefix is wrong :-) body uses my global 'file variable - should 
be prefix: func [filename][copy/part filename find/last filename 
"."]

maybe some solution based upon short parse rule could be produced 
too :-)

i guess parse-rule would be longer in this case. now trying

re-suffix: func [file suffix][append copy/part file find/last file 
"." suffix]

cute!

I'm tring to expand functions, but unfortunatly I'm not good in bind-magic 
so I've no success. I've got following code:

>> b: func [value][print ["value:" value]]
>> a: func [value][probe value]
>> append second :a compose [b (first :a)]
== [probe value b value]
>> a 1
1
** Script Error: value word has no context
** Where: a
** Near: b value

I've tried to bind it to 'a or 'value but without success. Can somebody 
help me?

!>f1: func[a[integer!]][?? a]
!>third :f1
== [a [integer!]]
!>f2: func third :f1 append second :f1 [print ["=" a]]     
!>source f2
f2: func [a [integer!]][?? a print ["=" a]]
!>f2 24
a: 24
= 24

(needs recent rebol for the [integer!]-part)

of course instead of third :f1 you can just copy the source for the 
argument-list, and maybe add locals.

volker it's not exactly what I needed but I can probably do it this 
way

I'll try it, when I get home and let you. Thanks

let you know

i thought so. you want to append something to the function body. 
and to make that use the functions variables, you have to re-func-ing.

but i read now again.

Oh, I did not know I need to re-func it

I'm trying to append something to feel/over so I need to make new, 
expanded 'over and than replace old 'over with the new one, if I 
understand you correctly