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authorJörg Frings-Fürst <debian@jff.email>2020-04-20 20:33:51 +0200
committerJörg Frings-Fürst <debian@jff.email>2020-04-20 20:33:51 +0200
commit6b986090d954dbac91bbb3c43ce7c3328c91a780 (patch)
tree34b34e41a3f7b7f4794c75be4482bb14695f36a9 /doc/RE
parent4216de6a3336cbc6dddb572cb7e6ab6193bf3729 (diff)
New upstream version 6.9.5upstream/6.9.5
Diffstat (limited to 'doc/RE')
-rw-r--r--doc/RE50
1 files changed, 31 insertions, 19 deletions
diff --git a/doc/RE b/doc/RE
index 599d2a6..f96efe7 100644
--- a/doc/RE
+++ b/doc/RE
@@ -1,6 +1,6 @@
-Oniguruma Regular Expressions Version 6.9.4 2019/10/31
+Oniguruma Regular Expressions Version 6.9.5 2020/04/09
-syntax: ONIG_SYNTAX_ONIGURUMA (default)
+syntax: ONIG_SYNTAX_ONIGURUMA (default syntax)
1. Syntax elements
@@ -21,19 +21,28 @@ syntax: ONIG_SYNTAX_ONIGURUMA (default)
\f form feed (0x0C)
\a bell (0x07)
\e escape (0x1B)
- \nnn octal char (encoded byte value)
- \o{17777777777} wide octal char (character code point value)
- \uHHHH wide hexadecimal char (character code point value)
- \xHH hexadecimal char (encoded byte value)
- \x{7HHHHHHH} wide hexadecimal char (character code point value)
- \cx control char (character code point value)
- \C-x control char (character code point value)
- \M-x meta (x|0x80) (character code point value)
- \M-\C-x meta control char (character code point value)
+ \nnn octal char (encoded byte value)
+ \xHH hexadecimal char (encoded byte value)
+ \x{7HHHHHHH} (1-8 digits) hexadecimal char (code point value)
+ \o{17777777777} (1-11 digits) octal char (code point value)
+ \uHHHH hexadecimal char (code point value)
+ \cx control char (code point value)
+ \C-x control char (code point value)
+ \M-x meta (x|0x80) (code point value)
+ \M-\C-x meta control char (code point value)
(* \b as backspace is effective in character class only)
+2.1 Code point sequences
+
+ Hexadecimal code point (1-8 digits)
+ \x{7HHHHHHH 7HHHHHHH ... 7HHHHHHH}
+
+ Octal code point (1-11 digits)
+ \o{17777777777 17777777777 ... 17777777777}
+
+
3. Character types
. any character (except newline)
@@ -132,6 +141,7 @@ syntax: ONIG_SYNTAX_ONIGURUMA (default)
{,n} at least 0 but no more than n times ({0,n})
{n} n times
+
reluctant
?? 0 or 1 times
@@ -141,6 +151,11 @@ syntax: ONIG_SYNTAX_ONIGURUMA (default)
{n,}? at least n times
{,n}? at least 0 but not more than n times (== {0,n}?)
+ {n}? is reluctant operator in ONIG_SYNTAX_JAVA and ONIG_SYNTAX_PERL only.
+ (In that case, it doesn't make sense to write so.)
+ In default syntax, /a{n}?/ === /(?:a{n})?/
+
+
possessive (greedy and does not backtrack once match)
?+ 1 or 0 times
@@ -148,8 +163,8 @@ syntax: ONIG_SYNTAX_ONIGURUMA (default)
++ 1 or more times
{n,m} (n > m) at least m but not more than n times
- {n,m}+, {n,}+, {n}+ are possessive operators in ONIG_SYNTAX_JAVA and
- ONIG_SYNTAX_PERL only.
+ {n,m}+, {n,}+, {n}+ are possessive operators in ONIG_SYNTAX_JAVA and
+ ONIG_SYNTAX_PERL only.
ex. /a*+/ === /(?>a*)/
@@ -279,15 +294,12 @@ syntax: ONIG_SYNTAX_ONIGURUMA (default)
(?=subexp) look-ahead
(?!subexp) negative look-ahead
+
(?<=subexp) look-behind
(?<!subexp) negative look-behind
- Subexp of look-behind must be fixed-width.
- But top-level alternatives can be of various lengths.
- ex. (?<=a|bc) is OK. (?<=aaa(?:b|cd)) is not allowed.
-
- In negative look-behind, capturing group isn't allowed,
- but non-capturing group (?:) is allowed.
+ * Cannot use Absent stopper (?~|expr) and Range clear
+ (?~|) operators in look-behind and negative look-behind.
* In look-behind and negative look-behind, support for
ignore-case option is limited. Only supports conversion