World: r3wp

let me fire up Rebo/View again

but how will this help me where I have a WORD that is holding that 
initial, partial, path ?

join to-path do path 'a

path: 't2/f
do join to-path do path 'a

;same error
>> t1: [a "one"]
== [a "one"]
>> t2: [f t1]
== [f t1]
>> pp: join 't2/f 'a
== t2/f/a
>> do pp
** Script Error: Cannot use path on word! value
** Where: halt-view
** Near: t2/f/a
>>

2.6.3 just ditched me again with that one ...

This is the limitation of evaluating paths.  'do does not evalute 
't1 when it is returned from 't2/f

I think 2.6.3 does not want 'path used as a word ;-)

so do you think that   
   to-path reduce [ my-path  'my-next-refinement]
the best that I can do?

If your interpreter chokes on 'join, then I guess so...

I could try just Rebol/Core and see if that make a difference

It is not very often that Rebol blows out on me ... I can't remember 
when last before I started looking at my functor issues

That's 3 times tonight with only 2 teeny blocks and 2 paths  and 
no do against any file and nothing added to user.r

ah-ha !
Works fine in Rebol/Core  ! 

path: 't2/f
do join to-path do path 'a

Nope.

Back to View and this time Rebol did not blow out of the water .... 

Is there a dump.log that I can look at see what these fatal errors 
have been ?

Not sure.  Try working with -- trace on

>> t1: [a "one"]
== [a "one"]
>> t2: [f t1]
== [f t1]
>> path: 't2/f
== t2/f
>> do join to-path do path 'a
== "one"
; thanks CHRIS

Hey, if it works : )

I would not have stumbled on the 
   do path
any too soon, I fear ... ;-)

It's not the most intuitive move, for sure.

I am adding 
   augpath: func [{augment path with a word}
to my armory

Now to find out what typo of mine is able to blow 2.6.3 outa the 
wadder

augpath: func [{ augment a PATH with a WORD }path 'word] [
      return join to-path reduce[path] :word]
; augpath t2/f a

oops!
IGnoring the needless return,  that is one word longer than

>> pword: func [path 'word /local blk] [
    to-path reduce[path :word]]
; ;-)

; I mean
 augpath: func [path 'word ] [
    to-path reduce[path :word]]

; but IN the interpreter, to use join
>> do join to-path do my-path 'a-further-refinement
; is terrific and has led me to
my-path:  to-path join reduce[ my-path ] 'a-deeper-tag

Nope 
another typo
  my-path: t2/f
That is trivial
It has to be 
  my-path: 't2/f
or
  my-path: to-path [t2 f]

JOIN does a reduce, so that's probably your problem. to-path reduce 
is not doing what you expect there, it's creating a path inside a 
path (no wonder it may crash :).

use append copy path word

also, you need to reduce your blocks above, because you have words 
in them, not subblocks.

Thanks.  I should also have used a type block in my func 

   augpath: func [ {augment a path with a word} path [path!] functor 
   [ word! ] /local p ] [

Once there are only subblocks it becomes trivial;  I have been trying 
to augment a path! series which starts with a block in which a tagged-word 
is bound to a block .  By augment the path I mean to return a path, 
not the result of evaluating the path
  t1: [ a-word-with-no-value-functor "one" ]

  t2: [ functor t1 ]  ; t1 is a word, not a block, but is bound to 
  a block at the time the path is extended into it ( if possible without 
  t2 being an object! )
  t2: context [ functor t1] ; also trivial

; this work fine for traversal
>> navpath: func [ pth [path!] 'wrd [word!] /local p42 ] [
[    p42: do pth
[    to-path reduce [p42 :wrd]]
>> pp: navpath path a
== t1/a
>> do pp
== "one"

where path was
path: to-path [ t2 f ]

>> t1
== [a "one"]
>> t2: context [f: t1]
>> t2/f
== [a "one"]
>> t2/f/a
== "one"
>> first t1
== a
>> get first t1
** Script Error: a has no value
** Where: halt-view
** Near: get first t1
>> get first third t2
== [a "one"]

>> do append copy 't2/f 'a
== "one"

if you want to have words instead of the actual blocks in your blocks, 
then you need to "evaluate" the path yourself, which is not too hard.

>> b1: [a b2 c b3]
== [a b2 c b3]
>> b2: [d b3]
== [d b3]
>> b3: [e 4]
== [e 4]
>> eval-path: func [path /local val] [
[    val: get first path
[    foreach elem next path [
[        val: select val elem
[        if word? val [val: get val]
[        ]
[    val
[    ]
>> eval-path 'b1/a/d/e
== 4

(this assumes all elements of the path are blocks)

I realized there was this traversal option using a lit-path! treated 
as a series! but it did not seem to if what I already had was a path! 
 held by a word and I wanted to 'extend' that value with a word.

This arises when the embedded word becomes bound to a different block. 
 In that case an OBJECT! looks to be the only option but then the 
WORDSs in the PATH come already bound to values and so are not 'functors' 
as are 'a 'd and 'e in your example.

I  want to construct a resultant valid path! from a valid path! + 
a lit-word where that word has no value but serves only as functor.

I had hoped that the func to-lit-path would be the answer, but I 
see now that the default Rebol DO path! evaluation precludes this 
kind of 'append'.

I should be able to use a modified version of your eval-path func 
to take as args a valid path! and a word!

My path idea is more like a 'tilde' than our '/' such that I can 
have
        ; blk/key~wrd1~wrd2~wrd3 ... ~wrd-n     ; e.g.,  
    path~wrd1~wrd-i~wrd-j ~wrd-k    ; becomes
; ...
    path2~wrd-m~wrd-n  ;  i.e.,
        ; blk/key/putative-confirmed-key~wrd-m~wrd-n   
PARSE is likely part of the answer if I go that TILDE route.
Once I have a lit-path! your eval-path is the traversal.
A blk of args to a func such as

  construct_dpath: func  [ dpath [lit-path!]  functor-words-blk  [block! 
  ]  /local v1 v2] [ 

should model my case OK and that dpath can be constructed by modified 
versions of your eval-path.  Thanks

hmm, i'm not really sure what your final goal is.

>> p: 'b1/a/d
== b1/a/d
>> append p 'e
== b1/a/d/e

then you can call eval-path on p

i still think it would be much simpler if you just had blocks instead 
of words there :-)

I have this harmless fixation on Oz, the language ;-)
It was a kinda prologue to my coming to Rebol   lol

i'll need to look at it someday... ;)

Hello, I'm trying to write my first program in REBOL, besides "Hello, 
World!", heh. Anyway, I am trying to take the output of the DOS ipconfig 
command and only grab the IP address for my local NIC out of it. 
I would like to display the IP address only in a window in a large 
font. I have played with the call command in REBOL and have been 
able to use call/output to write the output of the command to a text 
file. My question is what would be the best way of grabbing the IP 
address I need out of this text file? Maybe there is another way 
I should be approaching this too, I'm not sure? Your thoughts and 
suggestions are appreciated. :)

Paul;  For one you can skip the intermediate file.  Try
>> res: make string! 80   call/output "ipconfig" res
it'll place the stdout results right in the string res.

Then you have some options.  REBOL has  (to name but two) find and 
parse for this kind of work.

Also take a look at the following functions:

>> system/network/host
>> system/network/host-address

Great, thank you for the quick answers! I'll take a look at this 
new information. :)