World: r3wp
[Core] Discuss core issues
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BrianH 23-Mar-2008 [9586] | Is it recursive? |
[unknown: 5] 23-Mar-2008 [9587x9] | yes |
Doesn't take much | |
replace-all: func [series oldval newval /local sd][ sub-ic?: func [sd][ forall sd [ either equal? first sd oldval [ poke sd 1 newval ][ if series? first sd [sub-ic? first sd] ] ] ] sub-ic? series ] | |
was written for a particular use I had but not for general use. It will have some limitations to be a mezzanine | |
It was built rapidly off of another function that I built in TRETBASE. | |
If you see a series it doesn't work on let me know. | |
I see some errors in it already in the code that I should patch real quick | |
Here you go: | |
replace-all: func [series oldval newval /local sub-ic][ sub-ic: func [sd][ forall sd [ either equal? first sd oldval [ poke sd 1 newval ][ if series? first sd [sub-ic first sd] ] ] ] sub-ic series ] | |
BrianH 23-Mar-2008 [9596x2] | Not bad. You use an inner function for the recursion, which should allow you to go to greater recursion depth before running out of stack space. I'd change the series? to any-block?, and the EITHER IF to a CASE, and the FORALL to a WHILE, and add type specs to the outer function, and change /local sd to /local sub-ic?, but otherwise good stuff. |
Sorry, I wrote most of that before you posted your fixed version. | |
[unknown: 5] 23-Mar-2008 [9598x2] | There you BrianH.. You just thought of ways to improve it. I just whipped it up when we were discussing it from another function built for a different purpose. |
I like your recommendations also. Maybe I will change the ip-check? function I have in TRETBASE which this is based on. | |
BrianH 23-Mar-2008 [9600] | Be sure to change your oldval and newval references to get-words for safety. |
[unknown: 5] 23-Mar-2008 [9601x2] | Not sure I follow you. |
Oh so it doesn't evaluate them you mean. | |
BrianH 23-Mar-2008 [9603] | either equal? first sd :oldval [ poke sd 1 :newval |
[unknown: 5] 23-Mar-2008 [9604x6] | Yeah good point |
Did i spark your interest for changing the replace function? | |
If so I suggest you keep the replace function and make this an entirely different replace function. Call it replace-deep if you like. | |
Then just cut out out the /all from your current replace function and leave as is. | |
The reason is that I believe this will be more tasking on the stats/evals then replace is by far. | |
By the way that recursion method with the function inside the function is the only way I found to get round most of those stack errors you mentioned. | |
BrianH 23-Mar-2008 [9610] | Have you seen the replace function? We are getting to the point of diminishing returns on new features - too much complexity overhead. As it is, we are going to have to use APPLY in the R3 version just to add another option. |
[unknown: 5] 23-Mar-2008 [9611] | No I haven't really paid much attention to it. i know there was some discussion on the 2.7.6 discussions but i haven't followed R3 development much at all. |
BrianH 23-Mar-2008 [9612] | Do source replace - it's a good way to learn some interesting optimization techniques. |
[unknown: 5] 23-Mar-2008 [9613] | is it the same in 2.7.6 as it is in 2.7.5? I'm currently using 2.7.5. |
BrianH 23-Mar-2008 [9614] | No, it really isn't. The 2.7.6 REPLACE was one of the backports, as was EXTRACT. |
[unknown: 5] 23-Mar-2008 [9615x2] | Extract is in 2.7.5 also which is the one I was using. Maybe that is why we are on different pages on that issue. |
I'll check them out later. | |
BrianH 23-Mar-2008 [9617] | I didn't realize that you weren't using 2.7.6. I wrote REPLACE and EXTRACT in that release. |
[unknown: 5] 23-Mar-2008 [9618x3] | oh - lol. |
replace-all: func [series oldval newval /local sub-ic][ sub-ic: func [sd][ while [not tail? sd ][ either equal? first sd :oldval [ poke sd 1 :newval ][ if series? first sd [sub-ic first sd] ] sd: next sd ] ] sub-ic series series ] | |
>> replace-all b 2 1 == [[1] [[[1]]] [1]] >> stats/evals == [219 105 47] | |
BrianH 23-Mar-2008 [9621] | Do you really want to do this: >> replace-all ["1"] 1 2 == ["2"] Otherwise, change series? to any-block? |
[unknown: 5] 23-Mar-2008 [9622] | Actually, that is exactly what I want |
BrianH 23-Mar-2008 [9623x2] | replace-all: func [series oldval newval /local sub-ic][ sub-ic: func [sd][ while [not tail? sd ][ case [ equal? first sd :oldval [poke sd 1 :newval] series? first sd [sub-ic first sd] ] sd: next sd ] ] sub-ic series series ] |
CASE is faster than 2 comparisons with EITHER or IF. | |
[unknown: 5] 23-Mar-2008 [9625] | I recall you saying that before I never really checked it out. |
BrianH 23-Mar-2008 [9626] | I profile code patterns to see which is faster. |
[unknown: 5] 23-Mar-2008 [9627x3] | I think your case is messed up |
I think I had that if for a reason but not sure why | |
in the case of mine both conditions will not be true whereas in your case arrangment both can can't they? | |
BrianH 23-Mar-2008 [9630] | Not unless you use case/all. Did you have /case as an option to your function at some point? |
[unknown: 5] 23-Mar-2008 [9631x2] | all yeah I always forget that. |
Keep thinking of like switch when I see case and I use case often. | |
BrianH 23-Mar-2008 [9633] | It's more like cond from Lisp. |
[unknown: 5] 23-Mar-2008 [9634] | yeah I never used another language other than REBOL so I wouldn't know. |
BrianH 23-Mar-2008 [9635] | Wow. I've never heard that before. |
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