Hi Ladislav,
Don't you copy the body?
>> x: tail-func [a][either a <= 0 [20] [x a - 1]]
>> x2: tail-func [a][either a <= 0 [200] [x a - 1]]
>> x 3
== 20
>> x2 3
== 20
---
Ciao
Romano
----- Original Message -----
From: "Ladislav Mecir" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Thursday, November 22, 2001 4:39 PM
Subject: [REBOL] Re: tail-func: for the gurus
> Hi all,
>
> I changed the implementation of Tail-func to support the THROW attribute:
>
> tail-func: function [
> {Creates a tail-recursive function.}
> [catch]
> spec [block!] body [block!]
> ] [
> ic icb i item locals result does-body
> ] [
> use [new-locals stop] [
> stop: false
> locals: copy []
> icb: copy []
> i: 1
> parse spec [
> any [
> set item any-word! (
> append locals to word! :item
> append icb compose [
> error? set/any pick new-locals (i) get/any pick
> locals (i)
> ]
> i: i + 1
> ) | skip
> ]
> ]
> set [new-locals body] use locals copy/deep reduce [
> reduce [locals body]
> ]
> use [finish] [
> does-body: has [ret] compose [
> finish: [return get/any 'result]
> set/any 'ret do (reduce [body])
> finish: [get/any 'result]
> get/any 'ret
> ]
> append icb compose/deep [
> either stop [
> stop: false
> ] [
> until [
> stop: true
> error? set/any 'result (:does-body)
> stop
> ]
> stop: false
> do finish
> ]
> ]
> ]
> ic: func [
> {do body with locals in new context}
> [throw]
> locals
> ] icb
> throw-on-error [
> func spec reduce [:ic locals]
> ]
> ]
> ]
>
>
> --
> To unsubscribe from this list, please send an email to
> [EMAIL PROTECTED] with "unsubscribe" in the
> subject, without the quotes.
>
--
To unsubscribe from this list, please send an email to
[EMAIL PROTECTED] with "unsubscribe" in the
subject, without the quotes.
