FAQ 4.27 How can I access or change N characters of a string?

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4.27: How can I access or change N characters of a string?

    You can access the first characters of a string with substr(). To get
    the first character, for example, start at position 0 and grab the
    string of length 1.

            $string = "Just another Perl Hacker";
            $first_char = substr( $string, 0, 1 );  #  'J'

    To change part of a string, you can use the optional fourth argument
    which is the replacement string.

            substr( $string, 13, 4, "Perl 5.8.0" );

    You can also use substr() as an lvalue.

            substr( $string, 13, 4 ) =  "Perl 5.8.0";


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