[REBOL] Re: Problem with paren
From: carl:cybercraft at: 2-Feb-2003 9:37
Hi Patrick,
On 02-Feb-03, pat665 wrote:
> Hi List,
> I am trying to build a block including some parenthesis and I am
> surely missing something. It seems I am not able to transform the
> words into parens.
> See that:
> values: [ 7 "/" "(" 1 "+" 2 ")"] test: copy []
> foreach v values [either integer! = type? v [append test v] [append
> test to-word v]]
> I have tried 'compose, 'compose/deep but I am at a loss...
> Any clue?
At one point there you're attempting to have this in your test
block...
[ 7 / ( ]
which just won't work in REBOL, as you can't have half a paren.
One way around this would be to append a paren, then insert your
values into it. ie...
>> blk: []
== []
>> append/only blk make paren! []
== [()]
So far, so good, but when we try to append to the paren we get this...
>> append last blk 1
** Script Error: tail expected series argument of type: series port
** Where: append
** Near: insert tail series :value
yet, oddly, insert works...
>> insert last blk 1
== ()
>> blk
== [(1)]
(Is this a bug people?)
To get around that you could at first append a block then convert it
to a paren when you've appended what you need to. ie...
>> blk: []
== []
>> append/only blk []
== [[]]
>> append last blk 1
== [1]
>> change/only back tail blk to-paren last blk
== []
>> blk
== [(1)]
Have fun...
--
Carl Read
