FAQ 4.32: How do I strip blank space from the beginning/end of a string?

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4.32: How do I strip blank space from the beginning/end of a string?

    Although the simplest approach would seem to be

        $string =~ s/^\s*(.*?)\s*$/$1/;

    not only is this unnecessarily slow and destructive, it also fails with
    embedded newlines. It is much faster to do this operation in two steps:

        $string =~ s/^\s+//;
        $string =~ s/\s+$//;

    Or more nicely written as:

        for ($string) {

    This idiom takes advantage of the "foreach" loop's aliasing behavior to
    factor out common code. You can do this on several strings at once, or
    arrays, or even the values of a hash if you use a slice:

        # trim whitespace in the scalar, the array,
        # and all the values in the hash
        foreach ($scalar, @array, @hash{keys %hash}) {


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