[REBOL] Re: how to parse thru nested parens?
From: nitsch-lists:netcologne at: 11-Dec-2001 15:01
RE: [REBOL] how to parse thru nested parens?
Hi Pekr
[petr--krenzelok--trz--cz] wrote:
> Hi,
>
> I am building sms system and I would like to trace following occurance:
>
> comand(text info or parameters)
>
> however, I wold like following to be parsed correctly, so ignoring
> nested parens, e.g.:
>
> command(some params(some subparams), maybe some other params)
>
> Thanks a lot,
>
see %parse-code.r in the script-library:
REBOL [
Title: "Parse REBOL Source"
Author: "Carl Sassenrath"
File: %parse-code.r
Date: 30-May-2000
Purpose: {An example of how to parse REBOL source code.}
Category: [script util text 2]
]
parse-code: func [
"Parse REBOL source code."
text /local str new
] [
parse text blk-rule: [
some [; repeat until done
str:
newline |
#";" [thru newline | to end] new: (probe copy/part str new) |
[#"[" | #"("] blk-rule |
[#"]" | #")"] |
skip (set [value new] load/next str probe :value) :new
]
]
]
i think your parsing has to replace the [skip ..]-part.
beware, this is recursive and parse has no local variables for that.
so real processing needs some workaround.
whats the best way to to this?
based on this is a pretty-printer %clean-script.r and a colorizer %color-code.r
there.
note there seems to be an bug in the parser,
triggered by long rebol-scripts in %clean-script.r .
starts doubling "[" to "[[" with the scripts rest, and nobody knows why.
i replaced the 'some with 'any, now it runs stable.
but it does not warn anymore if parents are unbalanced.
> Cheers,
> -pekr-
>
-Volker
