Perl Requires Chilkat v11.1.0+

Regular Expression with Multiple Matches and Capture Groups

See more Regular Expressions Examples

Demonstrates a regular expression with multiple matches and capture groups for each match.

Note: Chilkat uses PCRE2. See PCRE2 Regular Expressions
Also see: PCRE2 Performance

Chilkat2 Perl

use strict;
use warnings;
use Chilkat2;

my $success = 0;

my $pattern = 'Name:\s+(\w+)\s+(\w+),\s+Email:\s+(\S+)';

my $sb = Chilkat2::StringBuilder->new;
my $crlf = 1;
$sb->AppendLine('Name: John Smith, Email: john.smith@example.com', $crlf);
$sb->AppendLine('Name: Jack Johnson, Email: jack.johnson@example.com', $crlf);
$sb->AppendLine('Name: Mary Adams, Email: mary.adams@example.com', $crlf);

print $sb->GetAsString(), "\n";

# We have the following string:
# Name: John Smith, Email: john.smith@example.com
# Name: Jack Johnson, Email: jack.johnson@example.com
# Name: Mary Adams, Email: mary.adams@example.com

my $json = Chilkat2::JsonObject->new;
$json->EmitCompact(0);

my $timeoutMs = 2000;
my $numMatches = $sb->RegexMatch($pattern, $json, $timeoutMs);
if ($numMatches < 0) {
    # Probably an error in the regular expression.
    # Suggestion: Use AI to help create and/or diagnose regular expressions.
    print $sb->LastErrorText, "\n";
    exit;
}

# Examine the matches:
print $json->Emit(), "\n";

# This is the JSON with the match information.
# See the JSON parsing code below to get the matched capture group values.

# {
#   "match": [
#     {
#       "group": [
#         {
#           "cap": "Name: John Smith, Email: john.smith@example.com",
#           "idx": 0,
#           "len": 47
#         },
#         {
#           "cap": "John",
#           "idx": 6,
#           "len": 4
#         },
#         {
#           "cap": "Smith",
#           "idx": 11,
#           "len": 5
#         },
#         {
#           "cap": "john.smith@example.com",
#           "idx": 25,
#           "len": 22
#         }
#       ]
#     },
#     {
#       "group": [
#         {
#           "cap": "Name: Jack Johnson, Email: jack.johnson@example.com",
#           "idx": 49,
#           "len": 51
#         },
#         {
#           "cap": "Jack",
#           "idx": 55,
#           "len": 4
#         },
#         {
#           "cap": "Johnson",
#           "idx": 60,
#           "len": 7
#         },
#         {
#           "cap": "jack.johnson@example.com",
#           "idx": 76,
#           "len": 24
#         }
#       ]
#     },
#     {
#       "group": [
#         {
#           "cap": "Name: Mary Adams, Email: mary.adams@example.com",
#           "idx": 102,
#           "len": 47
#         },
#         {
#           "cap": "Mary",
#           "idx": 108,
#           "len": 4
#         },
#         {
#           "cap": "Adams",
#           "idx": 113,
#           "len": 5
#         },
#         {
#           "cap": "mary.adams@example.com",
#           "idx": 127,
#           "len": 22
#         }
#       ]
#     }
#   ]
# }

# Important:  Capture group 0 always contains the entire match — that is, the portion of the input string that matches the full regular expression.

my $cap = '';
my $i = 0;
my $matchCount = $json->SizeOfArray('match');
while ($i < $matchCount) {
    print 'Match ', ($i + 1), ":\n";
    $json->I($i);
    my $j = 0;
    my $numCaptureGroups = $json->SizeOfArray('match[i].group');
    while ($j < $numCaptureGroups) {
        $json->J($j);
        $cap = $json->StringOf('match[i].group[j].cap');
        print $j, ': ', $cap, "\n";
        $j = $j + 1;
    }

    $i = $i + 1;
}

# Capture group 0 always contains the entire match — that is, the portion of the input string that matches the full regular expression.

# Output

# Match 1:
# 0: Name: John Smith, Email: john.smith@example.com
# 1: John
# 2: Smith
# 3: john.smith@example.com
# Match 2:
# 0: Name: Jack Johnson, Email: jack.johnson@example.com
# 1: Jack
# 2: Johnson
# 3: jack.johnson@example.com
# Match 3:
# 0: Name: Mary Adams, Email: mary.adams@example.com
# 1: Mary
# 2: Adams
# 3: mary.adams@example.com