Yes, but it's very bad practice, because it's just too easy to make errors, and it makes your code much less readable. You could use an array instead:

my @f = split(//, $s);
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A alternate way to split the string:

my @f = $s =~ /./gs;
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An example of how to manipulate the array:

print("\@f has ", scalar(@f), " elements:\n");
print("\$f[$_] = $f[$_]\n") for (0..$#f);
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