[REBOL] Re: Newbie: need help with COMPOSE
From: lmecir:mbox:vol:cz at: 13-Oct-2003 13:34
Hi Arie,
----- Original Message -----
From: "Arie van Wingerden"
> Hi list,
>
> below a extracted piece of program containing 2 times a "do rejoin".
> I tried hard to not use rejoin, but compose instead, but it did'nt work out properly.
> Could you show me how to rewrite the code in both cases?
>
> Thanks in advance,
> Arie van Wingerden
>
> http://home.zonnet.nl/rebolution
>
> ;;; ========================= Code follows here
> REBOL []
> ;
> ; This function extends a 2nd level object with a function
> ;
> add-affix-func: does [
> do rejoin [ "rules/" fxname ": "
> "make rules/" fxname " [ " ; Extend 2nd level object
> "rule" fxcount ": func" ; Function name
> "[ inword [ string! ] ]" ; Function spec block
> "[ print 200 ]"
> "]"
> ]
> ]
> ;
> ; Main program starts here
> ;
> fxname: "A" ; name of 2nd level object
> fxcount: 1 ; counter
> rules: make object! [] ; create 1st level object
> do rejoin [
> "rules: make rules [" ; create 2nd level object
> fxname ": make object! [ x: 100 ]]"
> ]
> probe rules ; show intermediate result
> input ; pause console
> add-affix-func ; extend 2nd level object
> probe rules ; show final result
> input ; pause console
>
I (and the documentation) suggest you to avoid doing strings. Try the code below:
add-affix-func: has [fxn] [
fxn: in rules fxname
set fxn make get fxn compose [
(to set-word! join "rule" fxcount) ; Function name
func [inword [string!]] ; Function spec block
[print 200]
]
]
fxname: 'A ; name of 2nd level object
fxcount: 1 ; counter
rules: make object! [] ; create 1st level object
rules: make rules compose [ ; create 2nd level object
(to set-word! fxname) make object! [x: 100]
]
probe rules ; show intermediate result
; input ; pause console
add-affix-func ; extend 2nd level object
probe rules ; show final result
; input ; pause console
-L
