Idiomatic Rebol
[1/4] from: emekamicro:gm:ail at: 2-Sep-2010 18:34
Hello All,
Please check if the below is idiomatic Rebol
my-last: func[series][
if empty? next series [return first series]
my-last next series
]
my-but-last: func [series] [
if empty? next next series [return series]
my-but-last next series
]
element-at: func[series n m][
if n = m [return first series]
element-at next series n add 1 m
]
element-wat: func [series n][
element-at series n 0
]
reverse-list: func [series new-series][
if empty? series [return new-series]
reverse-list next series join to-block first series new-series
]
count-list: func [series n][
if empty? series [return n]
count-list next series add 1 n
]
[2/4] from: dhsunanda:gm:ail at: 2-Sep-2010 20:33
Good game!
I've not looked at them all -- perhaps other will.
But the last two are easily replaced by standard REBOL functions:
> reverse-list: func [series new-series][
> if empty? series [return new-series]
> reverse-list next series join to-block first series new-series
> ]
>
Just use REVERSE:
reverse [1 2 a print]
== [print a 2 1]
> count-list: func [series n][
> if empty? series [return n]
> count-list next series add 1 n
> ]
>
Just use LENGTH?:
length? [1 2 a print]
== 4
Check out the dictionary of REBOL words for other things you can do with
a series:
http://www.rebol.com/docs/dictionary.html
Sunanda.
[3/4] from: emekamicro:gma:il at: 2-Sep-2010 20:47
Sunanda,
I am just solving exercises on
http://www.ic.unicamp.br/~meidanis/courses/mc336/2006s2/funcional/L-99_Ninety-Nine_Lisp_Problems.html,
using it to learn Rebol.
I do know that we have those words, but I have to have a means of learning.
Regards,
Emeka
On Thu, Sep 2, 2010 at 8:33 PM, Sunanda <dhsunanda-gmail.com> wrote:
[4/4] from: dhsunanda:g:mail at: 2-Sep-2010 23:23
Emeka wrote:
> I am just solving exercises on
Interesting set of problems.
Some will be one-worders -- using built-in REBOL functions.
Some will be a little trickier.
Many can be approached in two quite distinct ways:
1. threading together REBOL functions to solve the problem
2. using the PARSE dialect.
Mastering PARSE may take your REBOLling to a new level.
Do drop by here regularly to share solutions; I am sure the true gurus
will be only too happy to chip in with tweaks and improvements.
It could turn into a useful showcase for REBOL idioms.
Good luck!
Sunanda.