Unicode Regular Expressions in Perl

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Unicode Regular Expressions s/ / /g Nick Patch Shutterstock

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Perl has some of the best Unicode support today, especially with respect to regular expressions. Benjamin Peterson The Guts of Unicode in Python PyCon 2013

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UTF-8 encoded input

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UTF-8 encoded input ⇩ decode

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UTF-8 encoded input ⇩ decode ⇩ character string

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UTF-8 encoded input ⇩ decode ⇩ character string ⇩ hack… hack… hack…

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UTF-8 encoded input ⇩ decode ⇩ character string ⇩ hack… hack… hack… ⇩ encode

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UTF-8 encoded input ⇩ decode ⇩ character string ⇩ hack… hack… hack… ⇩ encode ⇩ UTF-8 encoded output

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use utf8;

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use utf8; $word =~ s{ (?: دابآ | هراب | یدنب | يدنب | نیرت | یزیر | يزیر | یزاس | يزاس | ییاه ) $}{}x;

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use utf8; $word =~ s{ (?: ия # definite articles for nouns: | ът # ∙ masculine | та # ∙ feminine | то # ∙ neutral | те # ∙ plural ) $}{}x;

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use open qw( :encoding(UTF-8) :std );

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use utf8; use open qw( :encoding(UTF-8) :std ); use Test::More tests => 66; use Lingua::Stem::UniNE::CS qw( stem ); is stem('zvířatech'), 'zvíř', 'rm -atech'; is stem('zvířatům'), 'zvíř', 'rm -atům'; is stem('zvířata'), 'zvíř', 'rm -ata'; is stem('zvířaty'), 'zvíř', 'rm -aty';

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decode_json($json)

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decode('UTF-8', $arg)

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use v5.12;

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use v5.14;

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use charnames ':full';

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use charnames ':full'; sub remove_kasra { my ($word) = @_; $word =~ s{ \N{ARABIC KASRA} $}{}x; return $word; }

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use v5.16; sub remove_kasra { my ($word) = @_; $word =~ s{ \N{ARABIC KASRA} $}{}x; return $word; }

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\d 123…

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\d 123… … ১২৩

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\d 123… … ১২৩ … ໑໒໓

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[0-9] 123…

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\w abc… 123… _

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\w abc… 123… _ αβγ… … かきく

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\w abc… 123… _ αβγ… … かきく …د ج ب

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[A-Za-z0-9_] abc… 123… _

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\b abc… 123… _ αβγ… … かきく …د ج ب

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\R LF (\n) CR (\r) FF (\f)

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\R LF (\n) CR (\r) FF (\f) CRLF (\r\n)

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\R LF (\n) CR (\r) FF (\f) CRLF (\r\n) NEL VT LS PS

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\X n ̈

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\X Spınal Tap ̈

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\X Spınal Tap ̈ n\N{COMBINING DIAERESIS}

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\X Spınal Tap ̈ n\N{COMBINING DIAERESIS} \r\n

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\p{ASCII}

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\P{ASCII}

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\p{General_Category=Letter}

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\p{Letter}

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\p{L}

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\pL

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L Letter M Mark N Number P Punctuation S Symbol Z Separator C Other

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S Symbol Sm Math_Symbol Sc Currency_Symbol Sk Modifier_Symbol So Other_Symbol

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\p{Script=Latin}

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\p{Latin}

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[\p{Hiragana} \p{Katakana} \p{Han} \p{Latin} \p{Common}]

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[\p{Hira} \p{Kana} \p{Hani} \p{Latn} \p{Common}]

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Arab Arabic Beng Bengali Deva Devanagari Egyp Egyptian hieroglyphs Ethi Ethiopic Grek Greek Hang Hangul …

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return $word if $word =~ s{ зи $}{г}x || $word =~ s{ е ( \p{Cyrl} ) и $}{я$1}x || $word =~ s{ ци $}{к}x || $word =~ s{ (?: та | ища ) $}{}x;

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use v5.18;

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(?[ ])

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(?[ \d - \p{ASCII} ])

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(?[ \d & \p{Thai} ])

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perlre — regex syntax perlrebackslash — regex escape sequences perlrecharclass — regex character classes perlunicode — Unicode features Lingua::Stem::UniNE — code examples

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@nickpatch