From: Jon Strait <jstrait@moonloop.net>
Cc: zsh workers <zsh-workers@sunsite.dk>
Subject: Re: PATCH: New options for the PCRE module (to replace my previous)
Date: Wed, 25 Mar 2009 04:21:36 -0700 [thread overview]
Message-ID: <49CA13C0.1070308@moonloop.net> (raw)
In-Reply-To: <20090325100256.33b614d3@news01>
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Peter Stephenson wrote:
> On Wed, 25 Mar 2009 02:20:02 -0700
> Jon Strait <jstrait@moonloop.net> wrote:
>
>> A few adjustments since last time, with documentation.
>>
>> No reset of the special variables is done on a match failure.
>>
>
> Er, I can't remember what Phil said (I haven't been following this in any
> detail), but the documentation now says variables aren't altered on a
> failure, so presumably that is now incorrect. I don't think this is
> crucial as long as it's documented correctly.
>
> Could you in any case send a documentation patch against the current source
> and with lines wrapped to 80 columns?
>
> Thanks.
>
>
No, I ended up keeping the original behavior: On match failure, none of
the special variables are modified (reset).
Here is the updated doc patch.
Please let me know if anything I added isn't clear enough. Thanks.
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[-- Attachment #2: mod_pcre.yo.patch --]
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--- mod_pcre-old.yo 2009-01-15 01:49:06.000000000 -0800
+++ mod_pcre.yo 2009-03-25 03:55:58.000000000 -0700
@@ -6,7 +6,7 @@
startitem()
findex(pcre_compile)
-item(tt(pcre_compile) [ tt(-aimx) ] var(PCRE))(
+item(tt(pcre_compile) [ tt(-aimxs) ] var(PCRE))(
Compiles a perl-compatible regular expression.
Option tt(-a) will force the pattern to be anchored.
@@ -15,6 +15,8 @@
tt(^) and tt($) will match newlines within the pattern.
Option tt(-x) will compile an extended pattern, wherein
whitespace and tt(#) comments are ignored.
+Option tt(-s) makes the dot metacharacter match all characters,
+including those that indicate newline.
)
findex(pcre_study)
item(tt(pcre_study))(
@@ -22,7 +24,8 @@
matching.
)
findex(pcre_match)
-item(tt(pcre_match) [ tt(-v) var(var) ] [ tt(-a) var(arr) ] var(string))(
+item(tt(pcre_match) [ tt(-v) var(var) ] [ tt(-a) var(arr) ] \
+[ tt(-n) var(offset) ] [ tt(-b) ] var(string))(
Returns successfully if tt(string) matches the previously-compiled
PCRE.
@@ -33,8 +36,38 @@
case it will set the array var(arr). Similarly, the variable
var(MATCH) will be set to the entire matched portion of the
string, unless the tt(-v) option is given, in which case the variable
-var(var) will be set.
-No variables are altered if there is no successful match.
+var(var) will be set.
+No variables are altered if there is no successful match.
+A tt(-n) option starts searching for a match from the
+byte var(offset) position in var(string). If the tt(-b) option is given,
+the variable var(ZPCRE_OP) will be set to an offset pair string,
+representing the byte offset positions of the entire matched portion
+within the var(string). For example, a var(ZPCRE_OP) set to "32 45" indicates
+that the matched portion began on byte offset 32 and ended on byte offset 44.
+Here, byte offset position 45 is the position directly after the matched
+portion. Keep in mind that the byte position isn't necessarily the same
+as the character position when UTF-8 characters are involved.
+Consequently, the byte offset positions are only to be relied on in the
+context of using them for subsequent searches on var(string), using an offset
+position as an argument to the tt(-n) option. This is mostly
+used to implement the "find all non-overlapping matches" functionality.
+
+A simple example of "find all non-overlapping matches":
+
+example(
+string="The following zip codes: 78884 90210 99513"
+pcre_compile -m "\d{5}"
+accum=()
+pcre_match -b -- $string
+while [[ $? -eq 0 ]] do
+ b=($=ZPCRE_OP)
+ accum+=$MATCH
+ pcre_match -b -n $b[2] -- $string
+done
+print -l $accum
+
+
+)
)
enditem()
next prev parent reply other threads:[~2009-03-25 11:23 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-03-25 9:20 Jon Strait
2009-03-25 10:02 ` Peter Stephenson
2009-03-25 11:21 ` Jon Strait [this message]
2009-03-25 11:30 ` Peter Stephenson
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