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	(...) capturing brackets
	[...] grouping brackets (non capturing)
	{...} closure (return value ignored unless assigned)
	<...> Assertion (does this thing match?)
	:...  introduces a meta-syntactic token (a modifier)

$0 is the match object. Assigning to $0 affects the return value of the RE

Built-in regular expression modifiers

Long Modifier	Short Modifier	Meaning
:cont	:c	Continue from where the previous match left off
:words	:w	Match a sequence of "words". Causes whitespace (which is normally ignored) to be replaced by \s+ between identifier and \s* anywhere else
:ignorecase	:i	Match all alphabetic characters in a case insensitive manner
:any	:a	returns a list of anywhere the pattern matches within the string regardless of overlap
:each	:e	apply the pattern iteratively ("each" time we can)
:once	:o	Match succeeds exactly once. To allow the RE to match again, execute the .reset() method on the RE object.
?	:p5	Perl 5 matching. Cause the RE to be interpreted using the Perl 5 rules
?	:u0	Level 0 Unicode support. A . (dot) matches bytes
?	:u1	Level 1 Unicode support. A . (dot) matches code points
?	:u2	Level 2 Unicode support. A . (dot) matches a grapheme
?	:u3	Level 3 Unicode support. What . (dot) matches is language dependent
?	:1st	only match the first occurance of the pattern
?	:2nd	only match the second occurance of the pattern
?	:3rd	only match the third occurance of the pattern
?	:4th	only match the fourth occurance of the pattern
?	:5th	only match the fifth occurance of the pattern
...	...	...
?	:1x	Match one time
?	:2x	Match two times
?	:3x	Match three times
...	...	...

Built-in assertions

assertion	meaning
<alpha>	matches any alphabetic character
<digit>	matches any numeric character
<sp>	matches a space character
<prior>	match whatever the most recently successful match did
<after pattern>	matches only after pattern (zero-width)
<before pattern>	matches only before pattern (zero-width)
<commit>	fails the match if backtracked to
<cut>	fails the match if backtracked to and removes the portion of the string that matched to that point
<fail>	causes the match to fail if reached
<null>	match nothing

to:

Scotts Perl 6 Notes A 5^?

Restore

November 20, 2003, at 08:45 AM by unknown -

Changed lines 45-46 from:

<after pattern>	match if the pattern occurs after pattern
<before pattern>	match if the pattern occurs before pattern

to:

<after pattern>	matches only after pattern (zero-width)
<before pattern>	matches only before pattern (zero-width)

Restore

November 20, 2003, at 08:41 AM by unknown -

Changed line 1 from:

include:Main.DisclaimerText^?

to:

Notes on http://www.perl.com/lpt/a/2002/06/04/apo5.html Apocalypse 5

Changed lines 3-50 from:

Describe Scotts Perl 6 Notes here.

to:

Brave new world

	(...) capturing brackets
	[...] grouping brackets (non capturing)
	{...} closure (return value ignored unless assigned)
	<...> Assertion (does this thing match?)
	:...  introduces a meta-syntactic token (a modifier)

$0 is the match object. Assigning to $0 affects the return value of the RE

Built-in regular expression modifiers

Long Modifier	Short Modifier	Meaning
:cont	:c	Continue from where the previous match left off
:words	:w	Match a sequence of "words". Causes whitespace (which is normally ignored) to be replaced by \s+ between identifier and \s* anywhere else
:ignorecase	:i	Match all alphabetic characters in a case insensitive manner
:any	:a	returns a list of anywhere the pattern matches within the string regardless of overlap
:each	:e	apply the pattern iteratively ("each" time we can)
:once	:o	Match succeeds exactly once. To allow the RE to match again, execute the .reset() method on the RE object.
?	:p5	Perl 5 matching. Cause the RE to be interpreted using the Perl 5 rules
?	:u0	Level 0 Unicode support. A . (dot) matches bytes
?	:u1	Level 1 Unicode support. A . (dot) matches code points
?	:u2	Level 2 Unicode support. A . (dot) matches a grapheme
?	:u3	Level 3 Unicode support. What . (dot) matches is language dependent
?	:1st	only match the first occurance of the pattern
?	:2nd	only match the second occurance of the pattern
?	:3rd	only match the third occurance of the pattern
?	:4th	only match the fourth occurance of the pattern
?	:5th	only match the fifth occurance of the pattern
...	...	...
?	:1x	Match one time
?	:2x	Match two times
?	:3x	Match three times
...	...	...

Built-in assertions

assertion	meaning
<alpha>	matches any alphabetic character
<digit>	matches any numeric character
<sp>	matches a space character
<prior>	match whatever the most recently successful match did
<after pattern>	match if the pattern occurs after pattern
<before pattern>	match if the pattern occurs before pattern
<commit>	fails the match if backtracked to
<cut>	fails the match if backtracked to and removes the portion of the string that matched to that point
<fail>	causes the match to fail if reached
<null>	match nothing

Restore

Page last modified on September 29, 2005, at 09:28 PM

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