If you'd like a non regex solution, try using index and substr which, while less flexible than regexen can be clearer/better in a few situations. 
my $str = "/One/Two/Three";
my @paths = ($str);

while ($paths[-1] =~ tr#/#/# > 1) {
    push @paths, substr($paths[-1], 0, rindex($paths[-1], '/'));
}

print "$_\n" for @paths;

[download]
A few points of explanation: $paths[-1] means the last element of the array. The tr function returns the number of characters it transformed. The rindex function returns the character number where a substring last appears and the substr function returns part of a string. The push function adds items to the end of an array.

All these things are in the documentation that comes with perl, you just have to put them together.

In reply to Re: Re: (bbfu) Re: Messing with (my head) a substring by repson
in thread Messing with a substring by psypete

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