AltME: Rebol School

Messages

Endo
Anyone already wrote a function something like REPLACE-DEEP (similar to COMPOSE/DEEP) which deeply replace any match in a given block:
>> REPLACE-DEEP [ 1 [  2 "one" [ 3 "one" <something-else> ] ] ] "one" "two"
== [ 1 [  2 "two" [ 3 "two" <something-else> ] ] ]
I know it's not difficult using PARSE, but if anyone has already wrote, I don't waste my time. Thanks in advance.
Rebolek
Endo
Ah thanks! I wrote mine, I'll compare them.
replace-deep: func [ series [series!] value1 value2 /local rule m] [
    rule: [
        some [
            into rule
            |
            m: any-type! (if :value1 = first m [probe m: insert remove m :value2] :m)
            |
            skip
        ]
    ]
    parse series rule
]

DocKimbel
replace-deep: func [s [any-block!] value new /local rule pos][
    parse s rule: [any [pos: value (pos/1: new) | into rule | skip]]
    s
]
Gregg
Niiiiice. :-)
All of them, that is.
Endo
I think all of them have some problems including mine.
Doc: Your version stuck if no match:
>> replace-deep x: [a] 1 2   ;waits for ever
My version stucks if new value is a block that includes the search value:
>> replace-deep x: [a b [b] b] 'a [a b a]  ;infinite loop
Rebolek: Your version doesn't work for some values
>> replace-deep3 x: [1 2] 2 3  ; x stays unchanged
Rebolek
Oh, integers...
DocKimbel
It might be very complicated to achieve it using PARSE in Rebol2 due to the lack of escaping mechanism for words and integers like QUOTE in Red and Rebol3.
In Red, this version passes all the tests:
replace-deep: func [s [any-block!] value new /local rule pos][
    rule: [any [pos: quote _ (pos/1: new) | into rule | skip]]
    rule/2/3: value
    parse s rule
    s
]
probe replace-deep x: [a] 1 2
probe replace-deep x: [a b [b] b] 'a [a b a]
probe replace-deep x: [1 2] 2 3
[a]
[[a b a] b [b] b]
[1 3]
Rebolek
Endo's replace function (m: any-type! and then check for values in paren!) can do it
Nenad, your version is missing  ANY-STRING! rule before INTO RULE rule to ignore string!s, otherwise INTO will try to parse inside them.
DocKimbel
Indeed, with an INSERT/ONLY instead of INSERT, it would pass the second test.
Any-string!: good point.
Endo: the [ | skip ] part of your rule looks superfluous.

PeterWood
How does the /only refinement of find work?
Rebolek
>> find [a b c d] [a]                
== [a b c d]
>> find/only [a b c d] [a]
== none
>> find/only [[a] b c d] [a]
== [[a] b c d]
Pekr
for nested blocks?
C: [ 1 [ 2 3 4] 5 6 ]
find/only C [2 3 4]     ;--- should be find/deep then imo :-)
PeterWood
Thanks Rebolek and Pekr

Endo
I wrote some optimization questions in munge! group but not directly related to MUNGE, so I'll be appriciated if anyone can take a look and give sme ideas.
Ashley
INSERTing into a [large] block! is significantly slower than APPENDing. Likewise, REMOVEing from the head is much slower than the tail. For this reason it is often faster to create a new block than modifying [entensively] an existing one.

Last message posted 187 weeks ago.