In your context I'm rather fond of the special variable $". Quoting from the docs

When an array or an array slice is interpolated into a double-quoted string or a similar context such as /.../ , its elements are separated by this value. Default is a space. For example, this:

    print "The array is: @array\n";
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is equivalent to this:

    print "The array is: " . join($", @array) . "\n";
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