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[Core] Discuss core issues

Fork
26-Sep-2010
[18441x3]
(In my currently-still-very-limited Ruby tinkering, I have liked 
this convention--and in fact, sort of wished there were some way 
of it being more than just a convention, but reflected in a contract 
which generated both the modifying and non-modifying variant of an 
operation.)
The learnability of consistency vs. the beauty of making the common 
cases and idioms look elegant.   But are those looks deceiving?  
English sure is a mess... but people find it effective.
Why not follow your INTO convention?  Couldn't you make UNIQUE/INTO?
Graham
26-Sep-2010
[18444x2]
consistency leads to a lower cognitive load for the programmer
the argument that sort modifies because you can always copy first 
is met by the retort that you can always assign afterwards
Fork
26-Sep-2010
[18446x2]
I think that Rebol already has the "i before e but not after q and 
sometimes z" philosophy, in that there are forces driving it that 
are something of the nature of what drives natural language design. 
 Purely consistent  languages which have no special adaptations to 
the "messy" world don't really need to be designed, they exist mathematically 
already.  They are more discovered than made.
Hence the catch-phrase "Inspired by theory, driven by practice." 
 Of course, then the question comes up of "whose practice?" when 
releases are being timed to Amiga announcements etc.
Graham
26-Sep-2010
[18448x2]
So, tell me .. sort in place is more expensive than not, so another 
series is already created somewhere ...
so, modifying the original series is likely to be a convention and 
not an optimization
Fork
26-Sep-2010
[18450x3]
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... ?
Graham
26-Sep-2010
[18453]
perhaps it's a feeling that refinements should be used for passing 
new arguments than modifying behaviour?
Nicolas
26-Sep-2010
[18454]
Does anyone else have trouble calling a file that has parentheses 
in it?
Graham
26-Sep-2010
[18455]
eg. ?
Nicolas
26-Sep-2010
[18456]
call %/d/something with (parentheses).mp3
Graham
26-Sep-2010
[18457]
and what happens for you?
Nicolas
26-Sep-2010
[18458x6]
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 {"}]]
Henrik
26-Sep-2010
[18464]
I don't agree to copy on sort.
Graham
26-Sep-2010
[18465x2]
Perhaps you want 'run and not 'call ?
Except 'run was only implemented in IOS
Nicolas
26-Sep-2010
[18467x7]
** 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]
Graham
26-Sep-2010
[18474]
use [ n ][ n: :now set 'now func [][ n + 1]]
Steeve
26-Sep-2010
[18475]
call: func [file] compose [(:call) quotate quotate to-local-file 
file]
Nicolas
26-Sep-2010
[18476]
wow
Steeve
26-Sep-2010
[18477]
magic :)
Andreas
26-Sep-2010
[18478]
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.
Gregg
26-Sep-2010
[18479]
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.
Steeve
26-Sep-2010
[18480]
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.
BrianH
26-Sep-2010
[18481x4]
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.
Janko
26-Sep-2010
[18485]
(((( 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 
))))
Fork
26-Sep-2010
[18486x2]
>> reducificate: func [value] [either series? :value [head remove/part 
reduce/into value value tail value] [reduce :value]]
Works for DEDUPLICATE also, no?
Steeve
26-Sep-2010
[18488]
uh ????
Fork
26-Sep-2010
[18489]
Modifying REDUCE variant based on REDUCE/INTO, as a general pattern, 
just wondering what the data loss is that BrianH is referring to.
Steeve
26-Sep-2010
[18490]
ah! reduce in place.
But what a pain (in the ...)