World: r3wp
[Parse] Discussion of PARSE dialect
older newer | first last |
Steeve 10-Nov-2008 [3133x4] | i'm wondering if special commands like (PUSH and POP) to save/restore the current index when entering in recursive rules would be usefull |
i had the case IIRC (i simulated th | |
i take an example: to simulate AND we do [here: rule :here] but it can't be used in a recursive manner. If we had PUSH and POP to save and restore the current Index depending the level of the recursion (in fact they are stack operations) So, we could write: AND: [push rule pop] | |
it could be very interesting and replace USE in many cases | |
Gabriele 11-Nov-2008 [3137] | would AND be equivalent to [use [success?] [[(success?: no) rule (success?: yes) fail | none] check (success?)]] ? |
Pekr 11-Nov-2008 [3138] | If it is equivalent, reading your rule, then I full agree to add AND :-) |
Gabriele 11-Nov-2008 [3139x3] | petr, it depends on how it's useful. i've never had to write that in the past 9 years or so :) |
also, the above is to be recursion safe. in most cases you can just use here: rule :here or something like that. | |
(or, even use [here] [here: rule :here] might be a better way to put it. i was trying to avoid the here: :here thing in the above :) | |
Pekr 11-Nov-2008 [3142] | here: :here concept is handy, understandable by beginners in parse like me. Adding recursion safety via USE is a good thing. Can't comment on AND usability, as I don't precisely understand its meaning ... |
BrianH 11-Nov-2008 [3143x3] | Gabriele, that would be one way to do AND (though Peta's workaround is probably the most efficient). |
AND is a lookahead function, inspired by TDPL theory. Apparently PARSE is close to TDPL or PEG grammars, but missing a little. | |
Well, Peta's additions and changes have been integrated and cleaned up. There are more clear guidelines for the project now. Still haven't added Gabriele's DO operation yet, though I now know how to do so. Anything else? | |
Steeve 11-Nov-2008 [3146] | Brian, good work until now ;-) |
Chris 11-Nov-2008 [3147] | Reflecting on words -- where does 'and come from? Reads a little awkwardly: cmd: [list [everything]] parse cmd ['list and block! into ['everything | 'something]] 'at might be more apt? parse cmd ['list at block! into ['everything]] parse cmd ['list not at [paren! | hash!] into ['everything]] |
Steeve 11-Nov-2008 [3148x4] | yeah i agree AND is not the best word for that job. i prefer [IF] it means what it does... But it's not a problem for me to keep AND |
for example: [IF block! INTO rule] | |
it's just a scam, all rules are optionnal within parse... (so IF or something else...) | |
if we take in acount his defintion: none consumming rule. Then something like REPLAY or REWIND is more adapted. | |
BrianH 11-Nov-2008 [3152x4] | AND comes from the use of & in the PEG syntax papers, but it could also be seen as being like the AND operator in REBOL, prefixed. |
Nonetheless, I agree that the names of AND and OF don't make much sense. The concept behind AND is sound though. | |
I have finally adapted Gabriele's DO proposal. Aside from naming issues, examples in need of explanation and any nagging questions we might be done here, with the exception of feedback from Carl about his proposals and any other issues. Anything else? | |
Added Chris's suggestion for AND to be named AT, and explained the advanced AND example (good luck!). If there aren't any more suggestions, I think this is ready to go to Carl. | |
Steeve 11-Nov-2008 [3156x2] | nothing about my ALL ? |
sob... | |
BrianH 11-Nov-2008 [3158] | I need to talk to Carl - it's a variant of his OF proposal, which probably isn't done yet. I'll bring it up :) |
Steeve 11-Nov-2008 [3159] | ok, good luck |
BrianH 11-Nov-2008 [3160] | I edited the OF proposal to provide a syntax description similar to the other proposals and added your suggestion, Steeve. |
Steeve 11-Nov-2008 [3161] | thanks |
Pekr 11-Nov-2008 [3162] | the parse doc is becoming scary precise :-) I hope Carl is not scared by the amount of requests :-) Can't wait to do similar job to low level View. Maybe we could start :-) |
BrianH 12-Nov-2008 [3163] | Maybe we're already working on low-level View :) |
Pekr 12-Nov-2008 [3164x4] | ah, can't believe that :-) But - Cyphre would be involved, no? And AFAIK he is not :-) |
Well then - transparent top window would be fine, but I think that more importantly - proper Unicode display should be a priority, and maybe looking at R3 alpha demo called button colors - it scrolls like molasses - there is either bug and there is more being redrawn than what is needed, or we have to think about other optimisations (e.g. I remember some 2 years ago Carl stating, that View might still render unnecessary things ...) | |
uh, wrong group, sorry ... | |
... another option I remember was to switch to compound rasterizer of AGG. And - REBOL timers are still substandard of what can be achieved imo ... But, as Carl said - those parts are going to be host part, hence open-source. We just need Carl to release sources. Hopefully it happens till I retire :-) (eventual replies to REBOL3 group, just wanted my comments to be at one channel) | |
BrianH 12-Nov-2008 [3168] | Cyphre is a member of the development world for the new GUI. |
[unknown: 5] 12-Nov-2008 [3169] | How many are working on REBOL3? |
Pekr 12-Nov-2008 [3170] | 1 - Carl .... |
[unknown: 5] 12-Nov-2008 [3171] | ;-) |
Pekr 12-Nov-2008 [3172x3] | In the past, there were Gabriele and Cyphre. Gab did initial VID3, http protocol and maybe other things. Cyphre did View kernel things - e.g. whole compositing engine was replaced by the better one - AGG based ... |
nowadays Henrik and BrianH are helping with VID 3.4. | |
uh, once again, I thought that I am in REBOL3 group ... | |
[unknown: 5] 12-Nov-2008 [3175] | heh. We can move this there. |
BrianH 12-Nov-2008 [3176x2] | Peta seems to have agreed with you, Chris, and changed the name of AND to AT. Things have settled down to grammar fixes. |
Carl has been notified that the proposals seem to have solidified. | |
Steeve 13-Nov-2008 [3178x3] | what doest it mean Brian ? (to have solidified) |
ah ok, you notified Carl, not he notified you | |
i hope he will keep some ideas... | |
BrianH 13-Nov-2008 [3181] | That would be nice. Check out the example at the end: No explicit failing, no position setting, no errors :) |
Steeve 13-Nov-2008 [3182] | Brian, it seems that when a file is parsed instead of a sub-directory, then your script duplicate the previous sub-directory |
older newer | first last |