in reply to Extract portion of string based on string separator

The following two also works: 

my ($y) = '/a/b/c/d/e/f' =~ m{^(/[^/]+/[^/]+/[^/]+)};

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my $y = join('', (split(qr{(?=/)}, '/a/b/c/d/e/f'))[0..2]);

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By the way, using $a is a bad habit. Declaring it as a lexical, doubly so.

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Re^2: Extract portion of string based on string separator
by Krambambuli (Curate) on Apr 26, 2007 at 08:07 UTC
    Depending a bit on whom eyes for your code goes, you might want to restyle ikegami's first suggestion above to something like 
    use strict;
use warnings;

my $path_head = _get_first_3( '/a/b/c/d/e/f' );

sub _get_first_3 {
    my ($path) = @_;

    my $path_part
        = qr{ [^/]+ }x; # whatever char except slash

    my $path_head_regex
        = qr{ ( \A                    # beginning of string
                ( / $path_part) {3} ) # /three/part/parts here
          }x;

    my ($head) = ($path =~ m{ $path_head_regex }x);

    return $head;
}

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[d/l]
      ikegami,GrandFather and Krambambuli,

      Thank you very much for the insightful solutions. I particularly liked Krambambuli's method of writing a subroutine for extracting the first n members. I have yet to understand how it works though.

      Best Regards,

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