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Name

SPVM::Regex - Regular Expression

Usage

  use Regex;
  
  # Pattern match
  {
    my $re = Regex->new("ab*c");
    my $string = "zabcz";
    my $match = $re->match("zabcz");
  }

  # Pattern match - UTF-8
  {
    my $re = Regex->new("あ+");
    my $string = "いあああい";
    my $match = $re->match($string);
  }

  # Pattern match - Character class and the nagation
  {
    my $re = Regex->new("[A-Z]+[^A-Z]+");
    my $string = "ABCzab";
    my $match = $re->match($string);
  }

  # Pattern match with captures
  {
    my $re = Regex->new("^(\w+) (\w+) (\w+)$");
    my $string = "abc1 abc2 abc3";
    my $match = $re->match($string);
    
    if ($match) {
      my $cap1 = $re->cap1;
      my $cap2 = $re->cap2;
      my $cpa3 = $re->cap3;
    }
  }
  
  # Replace
  {
    my $re = Regex->new("abc");
    my $string = "ppzabcz";
    
    # "ppzABCz"
    my $result = $re->replace($string, "ABC");
    
    my $replaced_count = $re->replaced_count;
  }

  # Replace with a callback and capture
  {
    my $re = Regex->new("a(bc)");
    my $string = "ppzabcz";
    
    # "ppzABbcCz"
    my $result = $re->replace($string, method : string ($re : Regex) {
      return "AB" . $re->cap1 . "C";
    });
  }

  # Replace global
  {
    my $re = Regex->new("abc");
    my $string = "ppzabczabcz";
    
    # "ppzABCzABCz"
    my $result = $re->replace_g($string, "ABC");
  }

  # Replace global with a callback and capture
  {
    my $re = Regex->new("a(bc)");
    my $string = "ppzabczabcz";
    
    # "ppzABCbcPQRSzABCbcPQRSz"
    my $result = $re->replace_g($string, method : string ($re : Regex) {
      return "ABC" . $re->cap1 . "PQRS";
    });
  }

  # . - single line mode
  {
    my $re = Regex->new("(.+)", "s");
    my $string = "abc\ndef";
    
    my $match = $re->match($string);
    
    unless ($match) {
      return 0;
    }
    
    unless ($re->cap1 eq "abc\ndef") {
      return 0;
    }
  }

Description

Regex provides regular expression.

Regex is a SPVM module.

The implementation is Google RE2.

Caution

SPVM is yet experimental status.

Regular Expression Syntax

See Google RE2 Syntax.

Fields

captures

  has captures : ro string[];

Get the captured strings.

match_start

  has match_start : ro int;

Get the start byte offset of the matched string.

match_length

  has match_length : ro int;

Get the length of the matched string.

replaced_count

  has replaced_count : ro int;

Get the replaced count.

Class Methods

new

  static method new : Regex ($pattern : string, $flags = undef : string)

Create a new Regex object and compile the regex pattern and the flags.

  my $re = Regex->new("^ab+c");
  my $re = Regex->new("^ab+c", "s");

Instance Methods

match

  method match : int ($string : string, $offset = 0 : int, $length = -1 : int)

The Alias for the following match_forward method.

  my $ret = $self->match_forward($string, \$offset, $length);

match_forward

  method match_forward : int ($string : string, $offset : int*, $length = -1 : int)

Execute pattern matching to the string range from the offset to the position proceeded by the length.

The offset is updated to the next starting position.

If the pattern matching is successful, return 1, otherwise return 0.

The string must be defined. Otherwise an exception will be thrown.

The offset + the length must be less than or equal to the length of the string. Otherwise an exception will be thrown.

The regex compililation is not yet performed. Otherwise an exception will be thrown.

replace

  method replace  : string ($string : string, $replace : object of string|Regex::Replacer, $offset = 0 : int, $length = -1 : int, $options = undef : object[])

The Alias for the following replace_common method.

  my $ret = $self->replace_common($string, $replace, \$offset, $length, $options);

replace_g

  method replace_g  : string ($string : string, $replace : object of string|Regex::Replacer, $offset = 0 : int, $length = -1 : int, $options = undef : object[])

The Alias for the following replace_common method.

  my $new_options_list = List->new($options);
  $new_options_list->push("global");
  $new_options_list->push(1);
  $options = $new_options_list->to_array;
  return $self->replace_common($string, $replace, \$offset, $length, $options);

replace_common

  method replace_common : string ($string : string, $replace : object of string|Regex::Replacer,
    $offset_ref : int*, $length = -1 : int, $options = undef : object[])

Replace the part of the pattern matching in the string range from the offset to the position proceeded by the length with the replacement string or callback.

The options can be used.

The string must be defined. Otherwise an exception will be thrown.

The replacement must be a string or a Regex::Replacer object. Otherwise an exception will be thrown.

The offset must be greater than or equal to 0. Otherwise an exception will be thrown.

The offset + the length must be less than or equal to the length of the string. Otherwise an exception will be thrown.

Internally match_forward is used for the pattern matching.

Options of replace_common

global

If global is a true value, the global replacement is performed.

cap1

  method cap1 : string ()

The alias for $re->captures->[1].

cap2

  method cap2 : string ()

The alias for $re->captures->[2].

cap3

  method cap3 : string ()

The alias for $re->captures->[3].

cap4

  method cap4 : string ()

The alias for $re->captures->[4].

cap5

  method cap5 : string ()

The alias for $re->captures->[5].

cap6

  method cap6 : string ()

The alias for $re->captures->[6].

cap7

  method cap7 : string ()

The alias for $re->captures->[7].

cap8

  method cap8 : string ()

The alias for $re->captures->[8].

cap9

  method cap9 : string ()

The alias for $re->captures->[9].

cap10

  method cap10 : string ()

The alias for $re->captures->[10].

cap11

  method cap11 : string ()

The alias for $re->captures->[11].

cap12

  method cap12 : string ()

The alias for $re->captures->[12].

cap13

  method cap13 : string ()

The alias for $re->captures->[13].

cap14

  method cap14 : string ()

The alias for $re->captures->[14].

cap15

  method cap15 : string ()

The alias for $re->captures->[15].

cap16

  method cap16 : string ()

The alias for $re->captures->[16].

cap17

  method cap17 : string ()

The alias for $re->captures->[17].

cap18

  method cap18 : string ()

The alias for $re->captures->[18].

cap19

  method cap19 : string ()

The alias for $re->captures->[19].

cap20

  method cap20 : string ()

The alias for $re->captures->[20].

Repository

SPVM::Regex - Github

Author

Yuki Kimoto

Contributors

Copyright & License

Copyright Yuki Kimoto 2022-2022, all rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.