World: r3wp

so, modifying the original series is likely to be a convention and 
not an optimization

Whether sort in place is more expensive or not depends on the fundamental 
operations upon which sort is built.  (This makes interview questions 
fun when people "know" the answers, because you say "oh.  well let's 
say you're on an architecture where a memory allocation costs 1000 
times more than a swap"... :P)

Anyway, the issue is about the program expressing the intent of the 
programmer and letting the system do the smartest thing under the 
hood given the understanding of what the programmer wanted, for the 
common cases.

Some thought process in Rebol design didn't make "ARITHMETICATE" 
or some variant of REDUCE which is modifying on its value target. 
 Instead, it was decided that REDUCE/INTO would be more interesting. 
 I'm just wondering what optimization logic makes DEDUPLICATE more 
interesting than UNIQUE/INTO... ?

perhaps it's a feeling that refinements should be used for passing 
new arguments than modifying behaviour?

Does anyone else have trouble calling a file that has parentheses 
in it?

eg. ?

call %/d/something with (parentheses).mp3

and what happens for you?

returns zero

but doesn't call it

actually the parentheses should be %28 and %29

here's one %/d/music/Astor Piazzolla/Astor Piazzolla - Adios nonino %28live%29.mp3

to get around it I use this function    call2: func [file][call quotate 
quotate to-local-file file]

quotate: func [str][rejoin [{"} str {"}]]

I don't agree to copy on sort.

Perhaps you want 'run and not 'call ?

Except 'run was only implemented in IOS

** Script Error: Feature not available in this REBOL

I'll just use call2 then.

Does anyone know how to redefine words?

e.g.  call: func [file] [system/words/call quotate quotate to-local-file 
file]

this doesn't work obviously. but do you get my meaning?

This works, but I can't get it into a redefine function.

old: context [call: get in system/words 'call]
call: func [file] [old/call quotate quotate to-local-file file]

use [ n ][ n: :now set 'now func [][ n + 1]]

call: func [file] compose [(:call) quotate quotate to-local-file 
file]

wow

magic :)

I also would love more internal consistency between mutating and 
non-mutating versions (and I'd personally like to have non-mutating 
versions be the default for all functions). But realistically, this 
kind of simplification will never be really an option for future 
REBOL development, I fear.

I don't think the Ruby ! sigil is particularly meaningful, so I wouldn't 
vote for that.


While having complete consistency might make for a more pure and 
mathematically beautiful language, I don't think that is REBOL's 
goal. REBOL's design has elements that exist to make things simpler 
and more obvious. You could argue that complete consistency would 
do that, but if you look at history, that's not the case. 


the argument that sort modifies because you can always copy first 
is met by the retort that you can always assign afterwards

 - You can always assign, but if you have other references to that 
 series, they wouldn't see the change. This can also cause unintended 
 side effects of course, which is the risk of modifying, but that's 
 part of REBOL too. :-\


We'll never please everyone. I'm OK with the current SORT and set-operation 
behavior.

There is absolutly no gain to copy by default. As Gregg stated: "you 
can easily COPY if you want, but it's hard to go the other way".

I'd say more: Default copies induces overheads you can't discard 
most of the time.

See UNIQUE. This function is not widely used in my apps, just because 
of that. Useless, because when we deals with huge series, we don't 
want to pay the COPY cost.

UNIQUE/into, good idea. DEDUPLICATE would use UNIQUE/into internally, 
but I can't think of any other use case. I'm sure others could.

No, that probably wouldn't work because you need the intermediate 
series so you don't have data loss. So, no use case so far.

The /into option wasn't added to many applicable natives, just the 
two that generate the most data in REBOL: REDUCE and COMPOSE. That 
might be a "biggest bang for the buck" thing, or maybe we just haven't 
gotten around to it yet. Or it might be a big hassle to add /into 
to a native, so to get it done you need to justify it with use cases.

Time will tell. Like it or not, REBOL is primarily built around mutating 
functions, except for functions that work on immutable values like 
integers. Most of the non-mutating functions we have are either built 
on their mutating counterparts in mezzanine, or are options of those 
functions. In a language with mutable values, mutating functions 
are the base. Functional-language fans tend to not like this (and 
when we start really implementing task-safe code they can say "I 
told you so!"). However, mutability can have advantages too, mostly 
in memory usage and performance, so it's a tradeoff.

(((( I know you don't agree with me, but I want a VM level way to 
define pure functions (that are guaranteed they can't change anything 
outside itself). 

Big future deal in rebol to me is in runtime code generation to express 
things and *code mobility* and there can't be any real mobility if 
the code I get can "get over the wire" can do anything to my system 
))))

>> reducificate: func [value] [either series? :value [head remove/part 
reduce/into value value tail value] [reduce :value]]

Works for DEDUPLICATE also, no?

uh ????

Modifying REDUCE variant based on REDUCE/INTO, as a general pattern, 
just wondering what the data loss is that BrianH is referring to.

ah! reduce in place.
But what a pain (in the ...)

/INTO is kind of novel and catchy, in terms of some of the optimization 
scenarios it allows for.  Making variants like "/NO-COPY" winds up 
looking like Rebol is doing a bad job of conventions like REDUCE 
vs REDUCE! ... as opposed to playing a whole different game.

It comes to my mind that reduce/into should not behave like inserting 
data but changing them.

Changing data if it's it's at the end of the container will simply 
add them.

But if it's at the head of the container, it will remplace them intead.
Probably more usefull, than the current behavior.

so that 
>> reduce/into data data

would simply do the job we all expecting. To reuse the same block. 
A reduce in place (rest in a peace)

We could only add one behavior for the /into option, and the insert 
behavior was the most basic.

Fork, your method would add the additional series allocation to the 
series itself, temporarily doubling its size (at most). And then 
the reallocated series would stay that size in memory even after 
DEDUPLICATE returns. So overall, worse.

Didn't you say that  UNIQUE has to copy the series anyway?  What's 
the difference?

Would doing the /INTO at the end of the series make it easier for 
the memory allocator to reclaim the space after the remove?

(May have misunderstand what you meant about the algorithm needing 
the original array and a temporary buffer the size of the output, 
as well as the output.)

Oh well, I dunno.  It's too hot here right now to think at all.  
92 indoors in the shade.