Hien Le wrote:
> Hello,
Hello,
> Given the string 'abcdefghijklmnopq', I wish to add a line break every
> 5 characters:
>
> abcde
> fghij
> klmno
> pq
$ perl -e'
my $foo = q[abcdefghijklmnopq];
print "$foo\n";
$foo =~ s/(.{0,5})/$1\n/g;
print $foo;
'
abcdefghijklmnopq
abcde
fghij
klmno
pq
> Method 1 below works, but my split() in method 2 captures 'something
> unexpected' at each match. Could someone please tell me what is split
> capturing that I am not seeing?
split( /X/, 'aXb' ) splits the string using the pattern and returns the list (
'a', 'b' ). split( /(X)/, 'aXb' ) splits the string using the pattern and
returns the list ( 'a', 'X', 'b' ). Everything not in the pattern is returned
in the list unless you use capturing parentheses and then everything in the
capturing parentheses is returned as well.
> My script:
> ==========
>
> #!/usr/bin/perl -w
>
> use strict;
>
> my $foo = 'abcdefghijklmnopq';
>
> # Method 1
> print( "\nMethod 1\n" );
> my $foo_length = length( $foo );
> for( my $i = 0; $i < $foo_length; $i += 5 )
> {
> my $bar1 = substr( $foo, $i, 5 );
> print( $bar1, "\n" );
> }
>
> # Method 2
> print( "\nMethod 2\n" );
> my @bar2 = split( /([a-z]{5})/, $foo ); # Captures white-spaces ?!?
> my $bar2_nb = @bar2;
> print( join( "\n", @bar2) );
> print( "\nElements in array = ", $bar2_nb, "\n" ); # 7 elements in the
> array.
>
> __END__
$ perl -e'
my $foo = q[abcdefghijklmnopq];
print "$foo\n";
my @bar = unpack q[(a5)*], $foo;
print map "$_\n", @bar;
'
abcdefghijklmnopq
abcde
fghij
klmno
pq
$ perl -e'
my $foo = q[abcdefghijklmnopq];
print "$foo\n";
my @bar = $foo =~ /.{0,5}/g;
print map "$_\n", @bar;
'
abcdefghijklmnopq
abcde
fghij
klmno
pq
John
--
use Perl;
program
fulfillment
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