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[Parse] Discussion of PARSE dialect

BrianH
24-Dec-2008
[3402]
Must go now - it's been fun :)
Maxim
24-Dec-2008
[3403]
yes cool.  ciao...
BrianH
29-Dec-2008
[3404]
I finished the Parse Proposals cleanup again. Enjoy!
GiuseppeC
29-Dec-2008
[3405x2]
I have read the cleanupped version. I like the "To-Thru" proposal 
to match for multiple ends but I have read that full grammar could 
not be used for "performance reasons".
However the proposal is really big and I think that implementing 
it would not be so easy and fast. Will we see it complete at the 
end of 2009 ? It is only Carl working on it :-(
BrianH
29-Dec-2008
[3407x2]
The real advantage to the TO/THRU enhancement comes when it lets 
you avoid creating charsets, which are a lot less useful with Unicode. 
It should be pretty easy to implement.
I think that the proposals are more than Carl was thinking they would 
be - apparently he had forgotten the previous proposal lists. I don't 
think that it will be too much of a problem though, as there are 
not really that many proposals that are likely to be accepted. Some 
are competing proposals, of which only one would be chosen. Also, 
there aren't that many proposals overall - they are just thoroughly 
specified.
GiuseppeC
29-Dec-2008
[3409x3]
Lets see how things evolves. Proposal are very interesting as they 
would easy a lot of work on building parse rules. Everything is silent 
apart some blog messages where I have read for the first time the 
word "Beta" connected with REBOL3.
(*ease)
Good night. Here in Italy is 20 past 1AM.
BrianH
29-Dec-2008
[3412x4]
My main concern is that Carl's main requirements of the proposal 
process have been ignored in some cases:

- That the proposals be concisely specified. The Purpose and Importance 
statements should be one sentence each.
- That there be no discussion of theory.
- That there be no specification of equivalent rules.
- That all discussions happen outside of the wiki.
- That this is a proposals page, not documentation.
While I appreciate the speculative documentation, it will need to 
be moved to another page once the proposals process is done.
As it is, I hope Carl will read a paper that long when he gets to 
the point of taking on PARSE.
The whole point of the proposals process was to prevent exactly what 
happened, so in that respect I failed.
PeterWood
29-Dec-2008
[3416]
If Carl sticks to his word in his intial request all the proposals 
will be rejected:


Each improvement will require test code be provided that would certify 
its correctness. No test code, no improvement. (Sorry... you often 
ask me what you can do to help. Please don't put the burden of testing 
such changes on me.)
BrianH
29-Dec-2008
[3417x3]
The test code hasn't been written yet.
The initial request was not the blog post - that came later.
The test code won't be in the wiki.
PeterWood
29-Dec-2008
[3420]
That doesn't appear logical to me. In his blog Carl specifically 
stated that proposals without test ocde would not be considered. 
You are saying the opposite.
BrianH
29-Dec-2008
[3421x3]
He didn't say that to me, nor did he specify any format for the test 
cases in his initial version of the proposals wiki.
We will have test cases once the test case syntax is specified.
They won't go in the wiki though, at least not the main page. The 
page is too big already.
Janko
31-Jan-2009
[3424]
Hi, I need am asking for some help with parse again... are there 
any detailed docs with examples about parse?
Josh
31-Jan-2009
[3425]
One that I used when I was learning was Brett's  http://www.codeconscious.com/rebol/parse-tutorial.html
Graham
31-Jan-2009
[3426x2]
Brett has lots of examples on parse
oops ... snap!
[unknown: 5]
31-Jan-2009
[3428]
http://www.rebol.com/docs/core23/rebolcore-15.html
Janko
31-Jan-2009
[3429x6]
aha, I remeber I learned a lot from that green page too.. thanks 
for links so far , I will read the pages and hopefully I will find 
something related to the problems I have
thanks paul for your link too, I couldn't find that page on google 
( I did the bret's one)
the last problem I had and steeve and oldes propsoed solutions... 
I got steeve's one but I don't get what "complement charset" in olde's 
does.. >>str: "a.b.c.d!e?f. " chars: complement charset ".!?" >> 
parse str [any chars tmp: to end (uppercase tmp)] str == "a.B.C.D!E?F. 
"<<
I think my problem is of this kind: http://www.mail-archive.com/[rebol-list-:-rebol-:-com]/msg16347.html
or in terms of Brett's examples: == true

>> a: copy "dog cat" parse a [ ANY [ thru "dog" (print 1) | thru 
"cat" (print 2) ] ]
1
2
== true

>> a: copy "cat dog" parse a [ ANY [ thru "dog" (print 1) | thru 
"cat" (print 2) ] ]
1
== true
basically similar problem that last time as I see now.. so by looking 
at that mailing list answers I have 2 solutions ... I use parse 3 
times on a string.. or maybe I use Ladislav's parseen which he said 
solves this.. but I don't yet know how :)
[unknown: 5]
31-Jan-2009
[3435]
What do you want to accomplish?
Janko
31-Jan-2009
[3436]
=heading=
[unknown: 5]
31-Jan-2009
[3437]
is that your answer?
Janko
31-Jan-2009
[3438x6]
no .. I am writing example
S WORKS IF IN THIS ORDER

=heading=

{comment some comment}

- line 1
- line 2

------------->

<h1>heading</h1>

<p>comment some comment</p>

<li>line 1<li>
<li>line 2</li>

THIS DOESN'T WORK

=heading=

{comment some comment}

=heading=

- line 1
- line 2

=heading=

{comment some comment}

ADDITIONAL (SIMILAR) PROBLEM

- line 1
+ line 2
+ line 3
- line 4
+ line 5

----------------->

<li class="a">line 1</li>
<li class="a">line 2</li>
...
------------> this arrow means that I convert that to that
basically it seems to me right now, PARSE is mega powerfull for anything 
that comes in somewhat PREDEFINED order, like dialects and many other 
things (I could do mulitple html extraction programs with it for 
some search project I was making without hitting this limitation 
- it was predefined order too).. but it seems to get limited at things 
that repeat/exchange themselves at random etc--
ups my last example with lists was bad
again ADDITIONAL (SIMILAR) PROBLEM

- line 1
+ line 2
+ line 3
- line 4
+ line 5

----------------->

<li class="minus">line 1</li>
<li class="plus">line 2</li>
<li class="plus">line 3</li>
<li class="minus">line 4</li>
...
Oldes
31-Jan-2009
[3444x3]
Complement:
>> c1: charset "1"
== make bitset! 64#{AAAAAAAAAgAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=}
>> find c1 "1"
== true
>> find c1 "2"
== none
>> c2: complement c1
== make bitset! 64#{/////////f////////////////////////////////8=}
>> find c2 "2"
== true
>> find c2 "1"
== none
>> ? complement
USAGE:
    COMPLEMENT value

DESCRIPTION:
     Returns the one's complement value.
     COMPLEMENT is an action value.

ARGUMENTS:

     value -- (Type: logic number char tuple binary string bitset image)
>> ? union
USAGE:
    UNION set1 set2 /case /skip size

DESCRIPTION:
     Creates a new set that is the union of the two arguments.
     UNION is a native value.

ARGUMENTS:
     set1 -- first set (Type: series bitset)
     set2 -- second set (Type: series bitset)

REFINEMENTS:
     /case -- Use case-sensitive comparison
     /skip -- Treat the series as records of fixed size
         size -- (Type: integer)
>>
Janko
31-Jan-2009
[3447]
Oldes thanks, I have looked at docs of complement, but the fact is 
that I don't know the meaning of word itself "Returns the one's complement 
value."   .. I imagine it returns everything except the values you 
give it, but that seems strange?
Oldes
31-Jan-2009
[3448x3]
convert-input: func[input [string!] /local stops rest opened-tags 
b e][
	probe input
	
	space: charset " ^-"
	stops: charset "-+^/"
	rest:  complement stops
	opened-li?: false

	parse/all input [
		some [

   () ;<-- to be able escape from the parse loop if there is any infinite 
   loop
			b: #"^/" e: (
				if opened-li? [
					e: change/part b "</li>^/" 1
					opened-li?: false
				]
			) 
			:e
			b: [
				#"-" any space e: (
					e: change/part b {<li class="minus">} e
					opened-li?: true
				)
				|
				#"+" any space e: (
					e: change/part b {<li class="plus">} e
					opened-li?: true
				)
			] :e
			| to #"^/"
			| end
		]
	]
	if opened-li? [
		append input "</li>"
	]
	input
]

probe convert-input {
- line 1
+ line 2
+ line 3
- line 4
+ line 5}
Now I see that the above example will require newline at start of 
the input. And that I'm not using the 'stops and 'rest at all:)
but is you use something like: any rest  it will give you any chars 
which are not defined in the 'stops charset
Janko
31-Jan-2009
[3451]
uh, that is some advanced parse :) .. I will need a couple of days 
to think it through