Split line with perl

问题

   title: Football team: Real Madrid stadium: Santiago Bernabeu players: Zinédine Zidane, Ronaldo, Luís Figo, Roberto Carlos, Raúl personnel: José Mourinho (head coach) Aitor Karanka (assistant coach (es))

How to split this with perl in:

   title: Football
   team: Real Madrid
   stadium: Santiago Bernabeu
   players: Zinédine Zidane Ronaldo Luís Figo Roberto Carlos Raúl
   personnel: José Mourinho (head coach) Aitor Karanka (assistant coach (es))

回答1:

Use a lookahead assertion:

say for split /(?=\w+:)/, $real_madrid_string;

Output

title: Football
team: Real Madrid
stadium: Santiago Bernabeu
players: Zinédine Zidane Ronaldo Luís Figo Roberto Carlos Raúl
personnel: José Mourinho (head coach) Aitor Karanka (assistant coach (es))

回答2:

This should do it. line.txt contains "title: Football team: Real Madrid stadium: Santiago Bernabeu players: Zinédine Zidane, Ronaldo, Luís Figo, Roberto Carlos, Raúl personnel: José Mourinho (head coach) Aitor Karanka (assistant coach (es))"

#!/usr/bin/perl
use strict;
use warnings;

my $fn="./line.txt";

open(IN,$fn);
my @lines=<IN>;

my %hash;
my $hashKey;

foreach my $line (@lines){
        $line=~s/\n//g;
        my @split1=split(" +",$line);
        foreach my $split (@split1){
                if($split=~m/:$/){
                        $hashKey=$split;
                }else{
                        if(defined($hash{$hashKey})){
                                $hash{$hashKey}=$hash{$hashKey}.$split." ";
                        }else{
                                $hash{$hashKey}=$split." ";
                        }
                }
        }
}

close(IN);


foreach my $key (keys %hash){
        print $key.":".$hash{$key}."\n";
}

回答3:

Contrary to what many are saying in their answers, you do not need lookahead (other than the Regex's own), you would only need to capture part of the delimiter, like so:

my @hash_fields = grep { length; } split /\s*(\w+):\s*/;

My full solution below:

my %handlers
    = ( players   => sub { return [ grep { length; } split /\s*,\s*/, shift ]; }
      , personnel => sub { 
            my $value = shift;
            my %personnel;
            # Using recursive regex for nested parens
            while ( $value =~ m/([^(]*)([(](?:[^()]+|(?2))*[)])/g ) {
                my ( $name, $role ) = ( $1, $2 );
                $role =~ s/^\s*[(]\s*//;
                $role =~ s/\s*[)]\s*$//;
                $name =~ s/^\s+//;
                $name =~ s/\s+$//;
                $personnel{ $role } = $name;
            }
            return \%personnel;
        }
      );
my %hash = grep { length; } split /(?:^|\s+)(\w+):\s+/, <DATA>;
foreach my $field ( keys %handlers ) { 
    $hash{ $field } = $handlers{ $field }->( $hash{ $field } );
}

Dump looks like this:

%hash: {
     personnel => {
                    'assistant coach (es)' => 'Aitor Karanka',
                    'head coach' => 'José Mourinho'
                  },
     players => [
                  'Zinédine Zidane',
                  'Ronaldo',
                  'Luís Figo',
                  'Roberto Carlos',
                  'Raúl'
                ],
     stadium => 'Santiago Bernabeu',
     team => 'Real Madrid',
     title => 'Football'
   }

回答4:

The best way is to use the split command using a zero-width lookahead:

$string = "title: Football team: Real Madrid stadium: Santiago Bernabeu players: Zinédine Zidane, Ronaldo, Luís Figo, Roberto Carlos, Raúl personnel: José Mourinho (head coach) Aitor Karanka (assistant coach (es))";

@split_string = split /(?=\b\w+:)/, $string;

回答5:

$string = "title: Football team: Real Madrid stadium: Santiago Bernabeu players: Zinédine Zidane, Ronaldo, Luís Figo, Roberto Carlos, Raúl personnel: José Mourinho (head coach) Aitor Karanka (assistant coach (es))";
@words = split(' ', $string);

@lines = undef;
@line = shift(@words);
foreach $word (@words)
{
    if ($word =~ /:/)
    {
        push(@lines, join(' ', @line));
        @line = undef;
    }
    else
    {
        push(@line, $word);
    }
}

print join("\n", @lines);

来源：https://stackoverflow.com/questions/7386215/split-line-with-perl